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  • Undefined symbols for C++0x lambdas?

    - by Austin Hyde
    I was just poking around into some new stuff in C++0x, when I hit a stumbling block: #include <list> #include <cstdio> using namespace std; template <typename T,typename F> void ForEach (list<T> l, F f) { for (typename list<T>::iterator it=l.begin();it!=l.end();++it) f(*it); } int main() { int arr[] = {1,2,3,4,5,6}; list<int> l (arr,arr+6); ForEach(l,[](int x){printf("%d\n",x);}); } does not compile. I get a load of undefined symbol errors. Here's make's output: i386-apple-darwin9-gcc-4.5.0 -std=c++0x -I/usr/local/include -o func main.cpp Undefined symbols: "___cxa_rethrow", referenced from: std::_List_node<int>* std::list<int, std::allocator<int> >::_M_create_node<int const&>(int const&&&) in ccPxxPwU.o "operator new(unsigned long)", referenced from: __gnu_cxx::new_allocator<std::_List_node<int> >::allocate(unsigned long, void const*) in ccPxxPwU.o "___gxx_personality_v0", referenced from: ___gxx_personality_v0$non_lazy_ptr in ccPxxPwU.o "___cxa_begin_catch", referenced from: std::_List_node<int>* std::list<int, std::allocator<int> >::_M_create_node<int const&>(int const&&&) in ccPxxPwU.o "operator delete(void*)", referenced from: __gnu_cxx::new_allocator<std::_List_node<int> >::deallocate(std::_List_node<int>*, unsigned long) in ccPxxPwU.o "___cxa_end_catch", referenced from: std::_List_node<int>* std::list<int, std::allocator<int> >::_M_create_node<int const&>(int const&&&) in ccPxxPwU.o "std::__throw_bad_alloc()", referenced from: __gnu_cxx::new_allocator<std::_List_node<int> >::allocate(unsigned long, void const*) in ccPxxPwU.o "std::_List_node_base::_M_hook(std::_List_node_base*)", referenced from: void std::list<int, std::allocator<int> >::_M_insert<int const&>(std::_List_iterator<int>, int const&&&) in ccPxxPwU.o ld: symbol(s) not found collect2: ld returned 1 exit status make: *** [func] Error 1 Why is this not working?

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  • find words in a hashset or treeset?

    - by icelated
    I am piping in a file and storing it into a treeset. I am trying to count unique words.. I am placing words that i dont want into a hashset. "a","the", "and" I want to check to see if the file contains those words, before i place them into the TreeSet.. i know i need some sort of if(word == find) ? i just dont know how to do it.. Sorry about formatting. its hard to get it correct after you paste. this is what i have.. import java.util.Scanner; import java.util.ArrayList; import java.util.TreeSet; import java.util.Iterator; import java.util.HashSet; public class Project1 { public static void main(String[] args) { Scanner sc = new Scanner(System.in); String word; String grab; int count = 0; int count2 =0; int count3 =0; int count4 =0; int number; TreeSet<String> a = new TreeSet<String>(); HashSet<String> find = new HashSet<String>(); System.out.println("Project 1\n"); find.add("a"); find.add("and"); find.add("the"); while (sc.hasNext()) { word = sc.next(); word = word.toLowerCase(); for(int i = 0; i < word.length(); i++ ) { if(Character.isDigit(word.charAt(i))) { count3++; } } //if( a.contains("a") ) //|| word.matches("and") || word.matches("the")|| word.contains("$")) //{ // count2++; // } a.add(word); if (word.equals("---")) { break; } } System.out.println("a size"); System.out.println(a.size()); // count = count2 - count; System.out.println("unique words"); System.out.println(a.size() - count2 - count3); System.out.println("\nbye..."); } }

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  • trouble with boost::filesystem::wrecursive_directory_iterator

    - by Dogmatixed
    I'm trying to write a program to help me manage my iTunes library, including removing duplicates and cataloging certain things. At this point I'm still just trying to get it to walk through all the folders, and have run into a problem: I have a small amount of Japanese music, where the artist and/or album is written in Japanese characters. Because of how iTunes arranges things in its library the directories contain these characters. "shouldn't be a problem, though." I thought, because the boost::filesystem library has a wide character version of its recursive iterator. but when I actually try to use it, it seems to completely stop when it hits the first Japanese char. complete stop as in it doesn't finish printing the line, no carriage return or anything. now, I'm still pretty new to programming, so I'm assuming it's my mistake, anyone know why this is happening? here's what I think is the relevant code: fs::wrecursive_directory_iterator end_it; int i; try { for(fs::wrecursive_directory_iterator rec_it(full_path); rec_it != end_it; ++rec_it) { for(i = 0; i < rec_it.level(); i++) { out << "\t"; } out << rec_it->string() << std::endl; } } catch(std::exception e) { out << "something went wrong: " << e.what(); } and from my output file, minus some of the path: /Test Libs/Combine /Test Libs/Lib1 /Test Libs/Lib1/02 Too Long.m4a /Test Libs/Lib1/03 Like a Hitman, Like a Dancer.mp3 /Test Libs/Lib1/A Certain Ratio /Test Libs/Lib1/A Certain Ratio/Beyond Punk! /Test Libs/Lib1/A Certain Ratio/Unknown Album /Test Libs/Lib1/A Certain Ratio/Unknown Album/Do The Du.mp3 /Test Libs/Lib1/A Certain Ratio/Unknown Album/Shack Up.mp3 /Test Libs/Lib1/ finally, what I expect: /Test Libs/Combine /Test Libs/Lib1 /Test Libs/Lib1/02 Too Long.m4a /Test Libs/Lib1/03 Like a Hitman, Like a Dancer.mp3 /Test Libs/Lib1/A Certain Ratio /Test Libs/Lib1/A Certain Ratio/Beyond Punk! /Test Libs/Lib1/A Certain Ratio/Unknown Album /Test Libs/Lib1/A Certain Ratio/Unknown Album/Do The Du.mp3 /Test Libs/Lib1/A Certain Ratio/Unknown Album/Shack Up.mp3 /Test Libs/Lib1/??? /Test Libs/Lib1/Bring it on /Test Libs/Lib1/04 Bring it on.mp3 any thoughts? Thanks.

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  • May volatile be in user defined types to help writing thread-safe code

    - by David Rodríguez - dribeas
    I know, it has been made quite clear in a couple of questions/answers before, that volatile is related to the visible state of the c++ memory model and not to multithreading. On the other hand, this article by Alexandrescu uses the volatile keyword not as a runtime feature but rather as a compile time check to force the compiler into failing to accept code that could be not thread safe. In the article the keyword is used more like a required_thread_safety tag than the actual intended use of volatile. Is this (ab)use of volatile appropriate? What possible gotchas may be hidden in the approach? The first thing that comes to mind is added confusion: volatile is not related to thread safety, but by lack of a better tool I could accept it. Basic simplification of the article: If you declare a variable volatile, only volatile member methods can be called on it, so the compiler will block calling code to other methods. Declaring an std::vector instance as volatile will block all uses of the class. Adding a wrapper in the shape of a locking pointer that performs a const_cast to release the volatile requirement, any access through the locking pointer will be allowed. Stealing from the article: template <typename T> class LockingPtr { public: // Constructors/destructors LockingPtr(volatile T& obj, Mutex& mtx) : pObj_(const_cast<T*>(&obj)), pMtx_(&mtx) { mtx.Lock(); } ~LockingPtr() { pMtx_->Unlock(); } // Pointer behavior T& operator*() { return *pObj_; } T* operator->() { return pObj_; } private: T* pObj_; Mutex* pMtx_; LockingPtr(const LockingPtr&); LockingPtr& operator=(const LockingPtr&); }; class SyncBuf { public: void Thread1() { LockingPtr<BufT> lpBuf(buffer_, mtx_); BufT::iterator i = lpBuf->begin(); for (; i != lpBuf->end(); ++i) { // ... use *i ... } } void Thread2(); private: typedef vector<char> BufT; volatile BufT buffer_; Mutex mtx_; // controls access to buffer_ };

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  • list of polymorphic objects

    - by LivingThing
    I have a particular scenario below. The code below should print 'say()' function of B and C class and print 'B says..' and 'C says...' but it doesn't .Any ideas.. I am learning polymorphism so also have commented few questions related to it on the lines of code below. class A { public: // A() {} virtual void say() { std::cout << "Said IT ! " << std::endl; } virtual ~A(); //why virtual destructor ? }; void methodCall() // does it matters if the inherited class from A is in this method { class B : public A{ public: // virtual ~B(); //significance of virtual destructor in 'child' class virtual void say () // does the overrided method also has to be have the keyword 'virtual' { cout << "B Sayssss.... " << endl; } }; class C : public A{ public: //virtual ~C(); virtual void say () { cout << "C Says " << endl; } }; list<A> listOfAs; list<A>::iterator it; # 1st scenario B bObj; C cObj; A *aB = &bObj; A *aC = &cObj; # 2nd scenario // A aA; // B *Ba = &aA; // C *Ca = &aA; // I am declaring the objects as in 1st scenario but how about 2nd scenario, is this suppose to work too? listOfAs.insert(it,*aB); listOfAs.insert(it,*aC); for (it=listOfAs.begin(); it!=listOfAs.end(); it++) { cout << *it.say() << endl; } } int main() { methodCall(); retrun 0; }

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  • subclassing QList and operator+ overloading

    - by Milen
    I would like to be able to add two QList objects. For example: QList<int> b; b.append(10); b.append(20); b.append(30); QList<int> c; c.append(1); c.append(2); c.append(3); QList<int> d; d = b + c; For this reason, I decided to subclass the QList and to overload the operator+. Here is my code: class List : public QList<int> { public: List() : QList<int>() {} // Add QList + QList friend List operator+(const List& a1, const List& a2); }; List operator+(const List& a1, const List& a2) { List myList; myList.append(a1[0] + a2[0]); myList.append(a1[1] + a2[1]); myList.append(a1[2] + a2[2]); return myList; } int main(int argc, char *argv[]) { QCoreApplication a(argc, argv); List b; b.append(10); b.append(20); b.append(30); List c; c.append(1); c.append(2); c.append(3); List d; d = b + c; List::iterator i; for(i = d.begin(); i != d.end(); ++i) qDebug() << *i; return a.exec(); } , the result is correct but I am not sure whether this is a good approach. I would like to ask whether there is better solution?

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  • How to get the result for return statement from JSON parsing?

    - by blankon91
    I've follow the code for parsing the value with JSON from here, but I get the problem in my return statement. I want to put the parsing result into my return statement. How to do that? Here is my code: public String MASUK(String user, String password) { SoapObject request = new SoapObject(WSDL_TARGET_NAMESPACE,OPERATION_NAME); PropertyInfo pi = new PropertyInfo(); pi.setName("ccduser"); pi.setValue(user); pi.setType(String.class); request.addProperty(pi); PropertyInfo pi2 = new PropertyInfo(); pi2.setName("password"); pi2.setValue(password); pi2.setType(String.class); request.addProperty(pi2); SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11); envelope.dotNet = true; envelope.setOutputSoapObject(request); HttpTransportSE httpTransport = new HttpTransportSE(SOAP_ADDRESS); try { httpTransport.call(SOAP_ACTION, envelope); SoapObject resultSOAP = (SoapObject) envelope.bodyIn; /* gets our result in JSON String */ String ResultObject = resultSOAP.getProperty(0).toString(); resultSOAP = (SoapObject) envelope.bodyIn; ResultObject = resultSOAP.getProperty(0).toString(); if (ResultObject.startsWith("{")) { // if JSON string is an object JSONObj = new JSONObject(ResultObject); Iterator<String> itr = JSONObj.keys(); while (itr.hasNext()) { String Key = (String) itr.next(); String Value = JSONObj.getString(Key); BundleResult.putString(Key, Value); // System.out.println(bundleResult.getString(Key)); } } else if (ResultObject.startsWith("[")) { // if JSON string is an array JSONArr = new JSONArray(ResultObject); System.out.println("length" + JSONArr.length()); for (int i = 0; i < JSONArr.length(); i++) { JSONObj = (JSONObject) JSONArr.get(i); BundleResult.putString(String.valueOf(i), JSONObj.toString()); // System.out.println(bundleResult.getString(i)); } } } catch (Exception exception) { } return null; }

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  • dynamic button in jsp

    - by kawtousse
    hi everyone, in my jsp i have a table constructed dynamically like the following: retour.append("<tr>"); try { s= HibernateUtil.currentSession(); tx=s.beginTransaction(); Query query = s.createQuery(HQL_QUERY); for(Iterator it=query.iterate();it.hasNext();) { if(it.hasNext()){ Dailytimesheet object=(Dailytimesheet)it.next(); retour.append("<td>" +object.getActivity() +"</td>"); retour.append("<td>" +object.getProjectCode() + "</td>"); retour.append("<td>" +object.getWAName() + "</td>"); retour.append("<td>" +object.getTaskCode() +"</td>"); retour.append("<td>" +object.getTimeFrom() +"</td>"); retour.append("<td>" +object.getTimeSpent() + "</td>"); retour.append("<td>" +object.getPercentTaskComplete() + "</td>"); if (droitdaccess) { retour.append(""); retour.append(""); retour.append(""); retour.append("<td bordercolor=#FFFFFF>"); retour.append("<input type=\"hidden\" id=\"id_"+nomTab+"_"+compteur+"\" value=\""+object.getIdDailyTimeSheet()+"\"/>"); retour.append("<img src=\"icon_delete.gif\" onClick=\"deletearowById('id_"+nomTab+"_"+compteur+"')\" style=\"cursor:pointer\" name=\"action\" value=\"deleting\" />"); retour.append("</td>"); } } compteur++; retour.append("</tr>"); } //terminer la table. retour.append ("</table>"); next to the table i want to display a button named send in order to send the table content. I do not really want to dispaly this button where the table is empty. So at least if the table is populated by nly one record i want that button being displayed. How should i deal in this case. Thanks.

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  • Using a map with set_intersection

    - by Robin Welch
    Not used set_intersection before, but I believe it will work with maps. I wrote the following example code but it doesn't give me what I'd expect: #include <map> #include <string> #include <iostream> #include <algorithm> using namespace std; struct Money { double amount; string currency; bool operator< ( const Money& rhs ) const { if ( amount != rhs.amount ) return ( amount < rhs.amount ); return ( currency < rhs.currency ); } }; int main( int argc, char* argv[] ) { Money mn[] = { { 2.32, "USD" }, { 2.76, "USD" }, { 4.30, "GBP" }, { 1.21, "GBP" }, { 1.37, "GBP" }, { 6.74, "GBP" }, { 2.55, "EUR" } }; typedef pair< int, Money > MoneyPair; typedef map< int, Money > MoneyMap; MoneyMap map1; map1.insert( MoneyPair( 1, mn[1] ) ); map1.insert( MoneyPair( 2, mn[2] ) ); map1.insert( MoneyPair( 3, mn[3] ) ); // (3) map1.insert( MoneyPair( 4, mn[4] ) ); // (4) MoneyMap map2; map1.insert( MoneyPair( 3, mn[3] ) ); // (3) map1.insert( MoneyPair( 4, mn[4] ) ); // (4) map1.insert( MoneyPair( 5, mn[5] ) ); map1.insert( MoneyPair( 6, mn[6] ) ); map1.insert( MoneyPair( 7, mn[7] ) ); MoneyMap out; MoneyMap::iterator out_itr( out.begin() ); set_intersection( map1.begin(), map1.end(), map2.begin(), map2.end(), inserter( out, out_itr ) ); cout << "intersection has " << out.size() << " elements." << endl; return 0; } Since the pair labelled (3) and (4) appear in both maps, I was expecting that I'd get 2 elements in the intersection, but no, I get: intersection has 0 elements. I'm sure this is something to do with the comparitor on the map / pair but can't figure it out.

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  • C++: Templates for static functions?

    - by Rosarch
    I have a static Utils class. I want certain methods to be templated, but not the entire class. How do I do this? This fails: #pragma once #include <string> using std::string; class Utils { private: template<class InputIterator, class Predicate> static set<char> findAll_if_rec(InputIterator begin, InputIterator end, Predicate pred, set<char> result); public: static void PrintLine(const string& line, int tabLevel = 0); static string getTabs(int tabLevel); template<class InputIterator, class Predicate> static set<char> Utils::findAll_if(InputIterator begin, InputIterator end, Predicate pred); }; Error: utils.h(10): error C2143: syntax error : missing ';' before '<' utils.h(10): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int utils.h(10): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int utils.h(10): error C2238: unexpected token(s) preceding ';' utils.h(10): error C2988: unrecognizable template declaration/definition utils.h(10): error C2059: syntax error : '<' What am I doing wrong? What is the correct syntax for this? Incidentally, I'd like to templatize the return value, too. So instead of: template<class InputIterator, class Predicate> static set<char> findAll_if_rec(InputIterator begin, InputIterator end, Predicate pred, set<char> result); I'd have: template<class return_t, class InputIterator, class Predicate> static return_t findAll_if_rec(InputIterator begin, InputIterator end, Predicate pred, set<char> result); How would I specify that: 1) return_t must be a set of some sort 2) InputIterator must be an iterator 3) InputIterator's type must work with return_t's type. Thanks.

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  • Infinite loop when adding a row to a list in a class in python3

    - by Margaret
    I have a script which contains two classes. (I'm obviously deleting a lot of stuff that I don't believe is relevant to the error I'm dealing with.) The eventual task is to create a decision tree, as I mentioned in this question. Unfortunately, I'm getting an infinite loop, and I'm having difficulty identifying why. I've identified the line of code that's going haywire, but I would have thought the iterator and the list I'm adding to would be different objects. Is there some side effect of list's .append functionality that I'm not aware of? Or am I making some other blindingly obvious mistake? class Dataset: individuals = [] #Becomes a list of dictionaries, in which each dictionary is a row from the CSV with the headers as keys def field_set(self): #Returns a list of the fields in individuals[] that can be used to split the data (i.e. have more than one value amongst the individuals def classified(self, predicted_value): #Returns True if all the individuals have the same value for predicted_value def fields_exhausted(self, predicted_value): #Returns True if all the individuals are identical except for predicted_value def lowest_entropy_value(self, predicted_value): #Returns the field that will reduce <a href="http://en.wikipedia.org/wiki/Entropy_%28information_theory%29">entropy</a> the most def __init__(self, individuals=[]): and class Node: ds = Dataset() #The data that is associated with this Node links = [] #List of Nodes, the offspring Nodes of this node level = 0 #Tree depth of this Node split_value = '' #Field used to split out this Node from the parent node node_value = '' #Value used to split out this Node from the parent Node def split_dataset(self, split_value): fields = [] #List of options for split_value amongst the individuals datasets = {} #Dictionary of Datasets, each one with a value from fields[] as its key for field in self.ds.field_set()[split_value]: #Populates the keys of fields[] fields.append(field) datasets[field] = Dataset() for i in self.ds.individuals: #Adds individuals to the datasets.dataset that matches their result for split_value datasets[i[split_value]].individuals.append(i) #<---Causes an infinite loop on the second hit for field in fields: #Creates subnodes from each of the datasets.Dataset options self.add_subnode(datasets[field],split_value,field) def add_subnode(self, dataset, split_value='', node_value=''): def __init__(self, level, dataset=Dataset()): My initialisation code is currently: if __name__ == '__main__': filename = (sys.argv[1]) #Takes in a CSV file predicted_value = "# class" #Identifies the field from the CSV file that should be predicted base_dataset = parse_csv(filename) #Turns the CSV file into a list of lists parsed_dataset = individual_list(base_dataset) #Turns the list of lists into a list of dictionaries root = Node(0, Dataset(parsed_dataset)) #Creates a root node, passing it the full dataset root.split_dataset(root.ds.lowest_entropy_value(predicted_value)) #Performs the first split, creating multiple subnodes n = root.links[0] n.split_dataset(n.ds.lowest_entropy_value(predicted_value)) #Attempts to split the first subnode.

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  • [C#] Problems with implementing generic IEnumerator and IComparable

    - by r0h
    Hi all! I'm working on an AVL Tree. The tree itself seems to be working but I need a iterator to walk through the values of the tree. Therefore I tried to implement the IEnumerator interace. Unfortunately I get a compile time error implementing IEnumerator and IComparable. First the code and below that the error. class AvlTreePreOrderEnumerator<T> : IEnumerator<T> where T :IComparable<T> { private AvlTreeNode<T> current = default(T); private AvlTreeNode<T> tree = null; private Queue<AvlTreeNode<T>> traverseQueue = null; public AvlTreePreOrderEnumerator(AvlTreeNode<T> tree) { this.tree = tree; //Build queue traverseQueue = new Queue<AvlTreeNode<T>>(); visitNode(this.tree.Root); } private void visitNode(AvlTreeNode<T> node) { if (node == null) return; else { traverseQueue.Enqueue(node); visitNode(node.LeftChild); visitNode(node.RightChild); } } public T Current { get { return current.Value; } } object IEnumerator.Current { get { return Current; } } public void Dispose() { current = null; tree = null; } public void Reset() { current = null; } public bool MoveNext() { if (traverseQueue.Count > 0) current = traverseQueue.Dequeue(); else current = null; return (current != null); } } The error given by VS2008: Error 1 The type 'T' cannot be used as type parameter 'T' in the generic type or method 'Opdr2_AvlTreeTest_Final.AvlTreeNode'. There is no boxing conversion or type parameter conversion from 'T' to 'System.IComparable'. For now I've not included the tree and node logic. I anybody thinks is necessary to resolve this probleem, just say so! Thx!

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  • C++ string sort like a human being?

    - by Walter Nissen
    I would like to sort alphanumeric strings the way a human being would sort them. I.e., "A2" comes before "A10", and "a" certainly comes before "Z"! Is there any way to do with without writing a mini-parser? Ideally it would also put "A1B1" before "A1B10". I see the question "Natural (human alpha-numeric) sort in Microsoft SQL 2005" with a possible answer, but it uses various library functions, as does "Sorting Strings for Humans with IComparer". Below is a test case that currently fails: #include <set> #include <iterator> #include <iostream> #include <vector> #include <cassert> template <typename T> struct LexicographicSort { inline bool operator() (const T& lhs, const T& rhs) const{ std::ostringstream s1,s2; s1 << toLower(lhs); s2 << toLower(rhs); bool less = s1.str() < s2.str(); std::cout<<s1.str()<<" "<<s2.str()<<" "<<less<<"\n"; return less; } inline std::string toLower(const std::string& str) const { std::string newString(""); for (std::string::const_iterator charIt = str.begin(); charIt!=str.end();++charIt) { newString.push_back(std::tolower(*charIt)); } return newString; } }; int main(void) { const std::string reference[5] = {"ab","B","c1","c2","c10"}; std::vector<std::string> referenceStrings(&(reference[0]), &(reference[5])); //Insert in reverse order so we know they get sorted std::set<std::string,LexicographicSort<std::string> > strings(referenceStrings.rbegin(), referenceStrings.rend()); std::cout<<"Items:\n"; std::copy(strings.begin(), strings.end(), std::ostream_iterator<std::string>(std::cout, "\n")); std::vector<std::string> sortedStrings(strings.begin(), strings.end()); assert(sortedStrings == referenceStrings); }

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  • C++: Trouble with Pointers, loop variables, and structs

    - by Rosarch
    Consider the following example: #include <iostream> #include <sstream> #include <vector> #include <wchar.h> #include <stdlib.h> using namespace std; struct odp { int f; wchar_t* pstr; }; int main() { vector<odp> vec; ostringstream ss; wchar_t base[5]; wcscpy_s(base, L"1234"); for (int i = 0; i < 4; i++) { odp foo; foo.f = i; wchar_t loopStr[1]; foo.pstr = loopStr; // wchar_t* = wchar_t ? Why does this work? foo.pstr[0] = base[i]; vec.push_back(foo); } for (vector<odp>::iterator iter = vec.begin(); iter != vec.end(); iter++) { cout << "Vec contains: " << iter->f << ", " << *(iter->pstr) << endl; } } This produces: Vec contains: 0, 52 Vec contains: 1, 52 Vec contains: 2, 52 Vec contains: 3, 52 I would hope that each time, iter->f and iter->pstr would yield a different result. Unfortunately, iter->pstr is always the same. My suspicion is that each time through the loop, a new loopStr is created. Instead of copying it into the struct, I'm only copying a pointer. The location that the pointer writes to is getting overwritten. How can I avoid this? Is it possible to solve this problem without allocating memory on the heap?

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  • Android Expandable List View Update

    - by Gaurav Arora
    I am implementing a chatting application, where I have made a service to listen all the presence changed. On the change of the presence I want to update the data and I am unable to update the data that is showing in the expandable list view. Please suggest me a means to do the same. public class UserMenuActivity extends ExpandableListActivity { private XMPPConnection connection; String name,availability,subscriptionStatus; TextView tv_Status; /** Variable Define here */ private String[] data = { "View my profile", "New Multiperson Chat", "New Broad Cast Message", "New Contact Category", "New Group", "Invite to CCM", "Search", "Expand All", "Settings", "Help", "Close" }; private String[] data_Contact = { "Rename Category","Move Contact to Category", "View my profile", "New Multiperson Chat", "New Broad Cast Message", "New Contact Category", "New Group", "Invite to CCM", "Search", "Expand All", "Settings", "Help", "Close" }; private String[] data_child_contact = { "Open chat", "Delete Contact","View my profile", "New Multiperson Chat", "New Broad Cast Message", "New Contact Category", "New Group", "Invite to CCM", "Search", "Expand All", "Settings", "Help", "Close" }; private String[] menuItem = { "Chats", "Contacts", "CGM Groups", "Pending","Request" }; private List<String> menuItemList = Arrays.asList(menuItem); private int commonGroupPosition = 0; private String etAlertVal; private DatabaseHelper dbHelper; private int categoryID, listPos; /** New Code here.. */ private ArrayList<String> groupNames; private ArrayList<ArrayList<ChildItems>> childs; private UserMenuAdapter adapter; private Object object; private String[] data2 = { "PIN Michelle", "IP Call" }; private ListView mlist2; private ImageButton mimBtnMenu; private LinearLayout mllpopmenu; private View popupView; private PopupWindow popupWindow; private AlertDialog.Builder alert; private EditText input; private TextView mtvUserName, mtvUserTagLine; private ExpandableListView mExpandableListView; public static List<CategoryDataClass> categoryList; private boolean menuType = false; private String childValContact=""; public static Context context; @Override public void onBackPressed() { if (mllpopmenu.getVisibility() == View.VISIBLE) { mllpopmenu.setVisibility(View.INVISIBLE); } else { if (CCMStaticVariable.CommonConnection.isConnected()) { CCMStaticVariable.CommonConnection.disconnect(); } super.onBackPressed(); } } @SuppressWarnings("unchecked") @Override public boolean onKeyDown(int keyCode, KeyEvent event) { if (keyCode == KeyEvent.KEYCODE_MENU) { if (mllpopmenu.getVisibility() == View.VISIBLE) { mllpopmenu.setVisibility(View.INVISIBLE); } else { if (commonGroupPosition >= 4 && menuType == true) { if(childValContact == ""){ mllpopmenu.setVisibility(View.VISIBLE); mlist2.setAdapter(new ArrayAdapter(UserMenuActivity.this, R.layout.listviewtext, R.id.tvMenuText, data_Contact)); }else{ mllpopmenu.setVisibility(View.VISIBLE); mlist2.setAdapter(new ArrayAdapter(UserMenuActivity.this, R.layout.listviewtext, R.id.tvMenuText, data_child_contact)); } } else if (commonGroupPosition == 0) { mllpopmenu.setVisibility(View.VISIBLE); mlist2.setAdapter(new ArrayAdapter(UserMenuActivity.this, R.layout.listviewtext, R.id.tvMenuText, data)); } } return true; } return super.onKeyDown(keyCode, event); } @Override public void onCreate(Bundle icicle) { super.onCreate(icicle); setContentView(R.layout.usermenulayout); dbHelper = new DatabaseHelper(UserMenuActivity.this); //this.context = context.getApplicationContext(); XMPPConn.getContactList(); connection = CCMStaticVariable.CommonConnection; Presence userPresence = new Presence(Presence.Type.available); userPresence.setPriority(24); userPresence.setMode(Presence.Mode.away); connection.sendPacket(userPresence); } @Override protected void onResume() { super.onResume(); Presence userPresence = new Presence(Presence.Type.available); userPresence.setPriority(24); userPresence.setMode(Presence.Mode.away); connection.sendPacket(userPresence); XMPPConn.getContactList(); setExpandableListView(); } public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) { if (groupPosition == 1 && childPosition == 0) { startActivity(new Intent(UserMenuActivity.this, InvitetoCCMActivity.class)); } else if (groupPosition == 1 && childPosition != 0) { Intent intent = new Intent(UserMenuActivity.this, UserChatActivity.class); intent.putExtra("userNameVal", XMPPConn.mfriendList.get(childPosition - 1).friendName); startActivity(intent); } else if (groupPosition == 2 && childPosition == 0) { startActivity(new Intent(UserMenuActivity.this, CreateGroupActivity.class)); } else if (groupPosition == 2 && childPosition != 0) { String GROUP_NAME = childs.get(groupPosition).get(childPosition) .getName().toString(); int end = GROUP_NAME.indexOf("("); CCMStaticVariable.groupName = GROUP_NAME.substring(0, end).trim(); startActivity(new Intent(UserMenuActivity.this, GroupsActivity.class)); } else if (groupPosition >= 4) { childValContact = childs.get(groupPosition).get(childPosition).getName().trim(); showToast("user==>"+childValContact, 0); } return false; } private void setExpandableListView() { /***###############GROUP ARRAY ############################*/ final ArrayList<String> groupNames = new ArrayList<String>(); groupNames.add("Chats (2)"); groupNames.add("Contacts (" + XMPPConn.mfriendList.size() + ")"); groupNames.add("CGM Groups (" + XMPPConn.mGroupList.size() + ")"); groupNames.add("Pending (1)"); XMPPConn.getGroup(); categoryList = dbHelper.getAllCategory(); /**Group From Sever*/ if (XMPPConn.mGroupList.size() > 0) { for (int g = 0; g < XMPPConn.mGroupList.size(); g++) { XMPPConn.getGroupContact(XMPPConn.mGroupList.get(g).groupName); groupNames.add(XMPPConn.mGroupList.get(g).groupName + "(" + XMPPConn.mGroupContactList.size()+ ")"); } } if(categoryList.size() > 0){ for (int cat = 0; cat < categoryList.size(); cat++) { groupNames.add(categoryList.get(cat).getCategoryName()+ "(0)"); } } this.groupNames = groupNames; /*** ###########CHILD ARRAY * #################*/ ArrayList<ArrayList<ChildItems>> childs = new ArrayList<ArrayList<ChildItems>>(); ArrayList<ChildItems> child = new ArrayList<ChildItems>(); child.add(new ChildItems("Alisha", "Hi",0)); child.add(new ChildItems("Michelle", "Good Morning",0)); childs.add(child); child = new ArrayList<ChildItems>(); child.add(new ChildItems("", "",0)); if (XMPPConn.mfriendList.size() > 0) { for (int n = 0; n < XMPPConn.mfriendList.size(); n++) { child.add(new ChildItems(XMPPConn.mfriendList.get(n).friendNickName, XMPPConn.mfriendList.get(n).friendStatus, XMPPConn.mfriendList.get(n).friendState)); } } childs.add(child); /************** CGM Group Child here *********************/ child = new ArrayList<ChildItems>(); child.add(new ChildItems("", "",0)); if (XMPPConn.mGroupList.size() > 0) { for (int grop = 0; grop < XMPPConn.mGroupList.size(); grop++) { child.add(new ChildItems( XMPPConn.mGroupList.get(grop).groupName + " (" + XMPPConn.mGroupList.get(grop).groupUserCount + ")", "",0)); } } childs.add(child); child = new ArrayList<ChildItems>(); child.add(new ChildItems("Shuchi", "Pending (Waiting for Authorization)",0)); childs.add(child); /************************ Group Contact List *************************/ if (XMPPConn.mGroupList.size() > 0) { for (int g = 0; g < XMPPConn.mGroupList.size(); g++) { /** Contact List */ XMPPConn.getGroupContact(XMPPConn.mGroupList.get(g).groupName); child = new ArrayList<ChildItems>(); for (int con = 0; con < XMPPConn.mGroupContactList.size(); con++) { child.add(new ChildItems( XMPPConn.mGroupContactList.get(con).friendName, XMPPConn.mGroupContactList.get(con).friendStatus,0)); } childs.add(child); } } if(categoryList.size() > 0){ for (int cat = 0; cat < categoryList.size(); cat++) { child = new ArrayList<ChildItems>(); child.add(new ChildItems("-none-", "",0)); childs.add(child); } } this.childs = childs; /** Set Adapter here */ adapter = new UserMenuAdapter(this, groupNames, childs); setListAdapter(adapter); object = this; mlist2 = (ListView) findViewById(R.id.list2); mimBtnMenu = (ImageButton) findViewById(R.id.imBtnMenu); mllpopmenu = (LinearLayout) findViewById(R.id.llpopmenu); mtvUserName = (TextView) findViewById(R.id.tvUserName); mtvUserTagLine = (TextView) findViewById(R.id.tvUserTagLine); //Set User name.. System.out.println("CCMStaticVariable.loginUserName===" + CCMStaticVariable.loginUserName); if (!CCMStaticVariable.loginUserName.equalsIgnoreCase("")) { mtvUserName.setText("" + CCMStaticVariable.loginUserName); } /** Expandable List set here.. */ mExpandableListView = (ExpandableListView) this .findViewById(android.R.id.list); mExpandableListView.setOnGroupClickListener(new OnGroupClickListener() { @Override public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) { XMPPConn.getContactList(); if (parent.isGroupExpanded(groupPosition)) { commonGroupPosition = 0; }else{ commonGroupPosition = groupPosition; } String GROUP_NAME = groupNames.get(groupPosition); int end = groupNames.get(groupPosition).indexOf("("); String GROUP_NAME_VALUE = GROUP_NAME.substring(0, end).trim(); if (menuItemList.contains(GROUP_NAME_VALUE)) { menuType = false; CCMStaticVariable.groupCatName = GROUP_NAME_VALUE; } else { menuType = true; CCMStaticVariable.groupCatName = GROUP_NAME_VALUE; } long findCatId = dbHelper.getCategoryID(GROUP_NAME_VALUE); if (findCatId != 0) { categoryID = (int) findCatId; } childValContact=""; showToast("Clicked on==" + GROUP_NAME_VALUE, 0); return false; } }); /** Click on item */ mlist2.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> arg0, View arg1, int pos,long arg3) { if (commonGroupPosition >= 4) { if(childValContact == ""){ if (pos == 0) { showAlertEdit(CCMStaticVariable.groupCatName); } /** Move contact to catgory */ if (pos == 1) { startActivity(new Intent(UserMenuActivity.this,AddContactCategoryActivity.class)); } }else{ if(pos == 0){ Intent intent = new Intent(UserMenuActivity.this,UserChatActivity.class); intent.putExtra("userNameVal",childValContact); startActivity(intent); } if(pos == 1){ XMPPConn.removeEntry(childValContact); showToast("Contact deleted sucessfully", 0); Intent intent = new Intent(UserMenuActivity.this,UserMenuActivity.class); } } } else { /** MyProfile */ if (pos == 0) { startActivity(new Intent(UserMenuActivity.this, MyProfileActivity.class)); } /** New multiperson chat start */ if (pos == 1) { startActivity(new Intent(UserMenuActivity.this, NewMultipersonChatActivity.class)); } /** New Broadcast message */ if (pos == 2) { startActivity(new Intent(UserMenuActivity.this, NewBroadcastMessageActivity.class)); } /** Click on add category */ if (pos == 3) { showAlertAdd(); } if (pos == 4) { startActivity(new Intent(UserMenuActivity.this, CreateGroupActivity.class)); } if (pos == 5) { startActivity(new Intent(UserMenuActivity.this, InvitetoCCMActivity.class)); } if (pos == 6) { startActivity(new Intent(UserMenuActivity.this, SearchActivity.class)); } if (pos == 7) { onGroupExpand(2); for (int i = 0; i < groupNames.size(); i++) { mExpandableListView.expandGroup(i); } } /** Click on settings */ if (pos == 8) { startActivity(new Intent(UserMenuActivity.this, SettingsActivity.class)); } if (pos == 10) { System.exit(0); } if (pos == 14) { if (mllpopmenu.getVisibility() == View.VISIBLE) { mllpopmenu.setVisibility(View.INVISIBLE); if (popupWindow.isShowing()) { popupWindow.dismiss(); } } else { mllpopmenu.setVisibility(View.VISIBLE); mlist2.setAdapter(new ArrayAdapter( UserMenuActivity.this, R.layout.listviewtext, R.id.tvMenuText, data)); } } } } }); } /** Toast message display here.. */ private void showToast(String msg, int time) { Toast.makeText(this, msg, time).show(); } public String showSubscriptionStatus(String friend){ return friend; } } Service.class public class UpdaterService extends Service { private XMPPConnection connection; String Friend; String user = ""; @Override public IBinder onBind(Intent arg0) { // TODO Auto-generated method stub return null; } @Override public void onCreate() { // Toast.makeText(this, "My Service Created", Toast.LENGTH_LONG).show(); super.onCreate(); } @Override public void onDestroy() { // TODO Auto-generated method stub super.onDestroy(); } @Override public void onStart(Intent intent, int startId) { // TODO Auto-generated method stub showToast("My Service Started", 0); connection = getConnection(); if (connection.isConnected()) { final Roster roster = connection.getRoster(); RosterListener r1 = new RosterListener() { @Override public void presenceChanged(Presence presence) { // TODO Auto-generated method stub XMPPConn.getContactList(); } @Override public void entriesUpdated(Collection<String> arg0) { // TODO Auto-generated method stub //notification("entriesUpdated"); } @Override public void entriesDeleted(Collection<String> arg0) { // TODO Auto-generated method stub //notification("entriesDeleted"); } @Override public void entriesAdded(Collection<String> arg0) { // TODO Auto-generated method stub Iterator<String> it = arg0.iterator(); if (it.hasNext()) { user = it.next(); } RosterEntry entry = roster.getEntry(user); if(entry.getType().toString().equalsIgnoreCase("to")){ int index_of_Alpha = Friend.indexOf("@"); String subID = Friend.substring(0, index_of_Alpha); notification("Hi "+subID+" wants to add you"); } } }; if (roster != null) { roster.setSubscriptionMode(Roster.SubscriptionMode.manual); System.out.println("subscription going on"); roster.addRosterListener(r1); } } else { showToast("Connection lost-", 0); } } protected void showToast(String msg, int time) { Toast.makeText(this, msg, time).show(); } private XMPPConnection getConnection() { return CCMStaticVariable.CommonConnection; } /** Notification manager */ private void notification(CharSequence message) { String ns = Context.NOTIFICATION_SERVICE; NotificationManager mNotificationManager = (NotificationManager) getSystemService(ns); int icon = R.drawable.ic_launcher; CharSequence tickerText = message; long when = System.currentTimeMillis(); Notification notification = new Notification(icon, tickerText, when); Context context = getApplicationContext(); CharSequence contentTitle = "CCM"; CharSequence contentText = message; Intent notificationIntent = new Intent(this, ManageNotification.class); notificationIntent.putExtra("Subscriber_ID",user ); PendingIntent contentIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0); notification.setLatestEventInfo(context, contentTitle, contentText, contentIntent); notification.flags |= Notification.FLAG_AUTO_CANCEL; final int HELLO_ID = 1; mNotificationManager.notify(HELLO_ID, notification); } } Here is my adapter class public class UserMenuAdapter extends BaseExpandableListAdapter { private ArrayList<String> groups; private ArrayList<ArrayList<ChildItems>> childs; private Context context; public LayoutInflater inflater; ImageView img_availabiliy; private static final int[] EMPTY_STATE_SET = {}; private static final int[] GROUP_EXPANDED_STATE_SET = {android.R.attr.state_expanded}; private static final int[][] GROUP_STATE_SETS = { EMPTY_STATE_SET, // 0 GROUP_EXPANDED_STATE_SET // 1 }; public UserMenuAdapter(Context context, ArrayList<String> groups, ArrayList<ArrayList<ChildItems>> childs) { this.context = context; this.groups = groups; this.childs = childs; inflater = LayoutInflater.from(context); } @Override public Object getChild(int groupPosition, int childPosition) { return childs.get(groupPosition).get(childPosition); } @Override public long getChildId(int groupPosition, int childPosition) { return (long) (groupPosition * 1024 + childPosition); } @Override public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) { View v = null; if (convertView != null) v = convertView; else v = inflater.inflate(R.layout.child_layout, parent, false); ChildItems ci = (ChildItems) getChild(groupPosition, childPosition); TextView tv = (TextView) v.findViewById(R.id.tvChild); tv.setText(ci.getName()); TextView tv2 = (TextView) v.findViewById(R.id.tvChild2); tv2.setText(ci.getDailyStatus()); img_availabiliy = (ImageView)v.findViewById(R.id.img_childlayout_AVAILABILITY); ImageView friendPics = (ImageView)v.findViewById(R.id.ivFriendPics); if(ci.getStatusState() == 1){ img_availabiliy.setImageResource(R.drawable.online); } else if(ci.getStatusState()==0){ img_availabiliy.setImageResource(R.drawable.offline); } else if (ci.getStatusState()==2) { img_availabiliy.setImageResource(R.drawable.away); } else if(ci.getStatusState()==3){ img_availabiliy.setImageResource(R.drawable.busy); } else{ img_availabiliy.setImageDrawable(null); } if((groupPosition == 1 && childPosition == 0)){ friendPics.setImageResource(R.drawable.inviteto_ccm); img_availabiliy.setVisibility(View.INVISIBLE); } else if(groupPosition == 2 && childPosition == 0){ friendPics.setImageResource(R.drawable.new_ccmgroup); img_availabiliy.setVisibility(View.VISIBLE); }else{ if(ci.getPicture()!= null){ Bitmap bitmap = BitmapFactory.decodeByteArray(ci.getPicture(), 0, ci.getPicture().length); bitmap = Bitmap.createScaledBitmap(bitmap, 50, 50, true); friendPics.setImageBitmap(bitmap); }else{ friendPics.setImageResource(R.drawable.avatar); } img_availabiliy.setVisibility(View.VISIBLE); } return v; } @Override public int getChildrenCount(int groupPosition) { return childs.get(groupPosition).size(); } @Override public Object getGroup(int groupPosition) { return groups.get(groupPosition); } @Override public int getGroupCount() { return groups.size(); } @Override public long getGroupId(int groupPosition) { return (long) (groupPosition * 1024); } @Override public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) { View v = null; if (convertView != null) v = convertView; else v = inflater.inflate(R.layout.group_layout, parent, false); String gt = (String) getGroup(groupPosition); TextView tv2 = (TextView) v.findViewById(R.id.tvGroup); if (gt != null) tv2.setText(gt); /**Set Image on group layout, Max/min*/ View ind = v.findViewById( R.id.explist_indicator); View groupInd = v.findViewById( R.id.llgroup); if( ind != null ) { ImageView indicator = (ImageView)ind; if( getChildrenCount( groupPosition ) == 0 ) { indicator.setVisibility( View.INVISIBLE ); } else { indicator.setVisibility( View.VISIBLE ); int stateSetIndex = ( isExpanded ? 1 : 0) ; Drawable drawable = indicator.getDrawable(); drawable.setState(GROUP_STATE_SETS[stateSetIndex]); } } if( groupInd != null ) { RelativeLayout indicator2 = (RelativeLayout)groupInd; if( getChildrenCount( groupPosition ) == 0 ) { indicator2.setVisibility( View.INVISIBLE ); } else { indicator2.setVisibility( View.VISIBLE ); int stateSetIndex = ( isExpanded ? 1 : 0) ; Drawable drawable2 = indicator2.getBackground(); drawable2.setState(GROUP_STATE_SETS[stateSetIndex]); } } return v; } @Override public boolean hasStableIds() { return true; } @Override public boolean isChildSelectable(int groupPosition, int childPosition) { return true; } public void onGroupCollapsed(int groupPosition) { } public void onGroupExpanded(int groupPosition) { } } I just want to update my list in ON PRESENCE CHANGED method in the Service class.. Please suggest me a means to do the same.

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  • scala: Adding attributes (odd and even rows) to xml table

    - by Debilski
    In a Lift application, I’d like to add a special tag which takes the <tbody> part of the next table and adds odd and even classes (for example) to each <tr> tag. Alternating, of course. While I have found a way to add another attribute to all <tr> tags, there are still a few problems left (see code below). First, it doesn’t work. cycle.next is called too often, so in the end, everything is an odd row. Other problems are that the code doesn’t exclude inner tables (so a nested <tr> would be transformed as well) and that it also affects the <thead> part of the table. Ideas to make this code work? (Of course, if there already is a lift-based solution – without jQuery – for this, I’ll gratefully take it.) class Loop(val strs: String*) { val stream_iter = Stream.continually(strs.toStream).flatten.iterator def next = stream_iter.next } val cycle = new Loop("even", "odd") val rr = new RewriteRule { override def transform(n: Node): Seq[Node] = n match { case elem : Elem => elem match { case Elem(_, "tr", att @ _, _, _*) => elem % Attribute(None, "class", Text( List(att.get("class").getOrElse("").toString, cycle.next).reduceLeft(_+" "+_).trim ), Null) toSeq case other => other } case other => other } } val rt = new RuleTransformer(rr) val code = <table> <thead><tr><td>Don’t</td><td>transform this</td></tr></thead> <tbody> <tr class="otherclass"> <td>r1c1</td><td>r1c2</td> </tr> <tr> <td>r2c1</td><td>r2c2</td> </tr> <tr> <td>r3c1</td><td>r3c2</td> </tr> </tbody> </table> println(rt(code))

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  • what is the wrong with this code"length indicator implementation" ?

    - by cj
    Hello, this is an implementation of length indicator field but it hang and i think stuck at a loop and don't show any thing. // readx22.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include "iostream" #include "fstream" #include "stdio.h" using namespace std; class Student { public: string id; size_t id_len; string first_name; size_t first_len; string last_name; size_t last_len; string phone; size_t phone_len; string grade; size_t grade_len; void read(fstream &ven); void print(); }; void Student::read(fstream &ven) { size_t cnt; ven >> cnt; id_len=cnt; id.reserve( cnt ); while ( -- cnt ) { id.push_back( ven.get() ); } ven >> cnt; first_len=cnt; first_name.reserve( cnt ); while ( -- cnt ) { first_name.push_back( ven.get() ); } ven >> cnt; last_len=cnt; last_name.reserve( cnt ); while ( -- cnt ) { last_name.push_back( ven.get() ); } ven >> cnt; phone_len=cnt; phone.reserve( cnt ); while ( -- cnt ) { phone.push_back( ven.get() ); } ven >> cnt; grade_len=cnt; grade.reserve( cnt ); while ( -- cnt ) { grade.push_back( ven.get() ); } } void Student::print() { // string::iterator it; for ( int i=0 ; i<id_len; i++) cout << id[i]; } int main() { fstream in; in.open ("fee.txt", fstream::in); Student x; x.read(in); x.print(); return 0; } thanks

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  • string s; &s+1; Legal? UB?

    - by John Dibling
    Consider the following code: #include <cstdlib> #include <iostream> #include <string> #include <vector> #include <algorithm> using namespace std; int main() { string myAry[] = { "Mary", "had", "a", "Little", "Lamb" }; const size_t numStrs = sizeof(myStr)/sizeof(myAry[0]); vector<string> myVec(&myAry[0], &myAry[numStrs]); copy( myVec.begin(), myVec.end(), ostream_iterator<string>(cout, " ")); return 0; } Of interest here is &myAry[numStrs]: numStrs is equal to 5, so &myAry[numStrs] points to something that doesn't exist; the sixth element in the array. There is another example of this in the above code: myVec.end(), which points to one-past-the-end of the vector myVec. It's perfecly legal to take the address of this element that doesn't exist. We know the size of string, so we know where the address of the 6th element of a C-style array of strings must point to. So long as we only evaluate this pointer and never dereference it, we're fine. We can even compare it to other pointers for equality. The STL does this all the time in algorithms that act on a range of iterators. The end() iterator points past the end, and the loops keep looping while a counter != end(). So now consider this: #include <cstdlib> #include <iostream> #include <string> #include <vector> #include <algorithm> using namespace std; int main() { string myStr = "Mary"; string* myPtr = &myStr; vector<string> myVec2(myPtr, &myPtr[1]); copy( myVec2.begin(), myVec2.end(), ostream_iterator<string>(cout, " ")); return 0; } Is this code legal and well-defined? It is legal and well-defined to take the address of an array element past the end, as in &myAry[numStrs], so should it be legal and well-defined to pretend that myPtr is also an array?

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  • Udp server sending only 0 bytes of data

    - by mawia
    Hi all, This is a simple Udp server.I am trying to transmit data to some clients,but unfortunetly it is unable to transmit data.Though send is running quite successfully but it is returning with a return value meaning it has send nothing.On the client they are receiving but again obviously,zero bytes. void* UdpServerStreamToClients(void *fileToServe) { int sockfd,n=0,k; struct sockaddr_in servaddr,cliaddr; socklen_t len; char dataToSend[1000]; sockfd=socket(AF_INET,SOCK_DGRAM,0); bzero(&servaddr,sizeof(servaddr)); servaddr.sin_family = AF_INET; servaddr.sin_addr.s_addr=htonl(INADDR_ANY); servaddr.sin_port=htons(32000); bind(sockfd,(struct sockaddr *)&servaddr,sizeof(servaddr)); FILE *fp; if((fp=fopen((char*)fileToServe,"r"))==NULL) { printf("can not open file "); perror("fopen"); exit(1); } int dataRead=1; while(dataRead) { len = sizeof(cliaddr); if((dataRead=fread(dataToSend,1,500,fp))<0) { perror("fread"); exit(1); } //sleep(2); for(list<clientInfo>::iterator it=clients.begin();it!=clients.end();it++) { cliaddr.sin_family = AF_INET; inet_aton(inet_ntoa(it->addr.sin_addr),&cliaddr.sin_addr); cliaddr.sin_port = htons(it->udp_port); n=sendto(sockfd,dataToSend,sizeof(dataToSend),0,(struct sockaddr *)&cliaddr,len); cout<<"number of bytes send by udp: "<< n << endl; printf("SEND this message %d : %s to %s :%d \n",n,dataToSend,inet_ntoa(cliaddr.sin_addr), ntohs(cliaddr.sin_port)); } } } I am checking the value of sizeof(dataTosend) and it is pretty much as expected ie thousand ie the size of buffer. Are you people seeing some possible flaw in it. All of the help in this regard will be appreciated. Thanks!

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  • Mutable objects and hashCode

    - by robert
    Have the following class: public class Member { private int x; private long y; private double d; public Member(int x, long y, double d) { this.x = x; this.y = y; this.d = d; } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + x; result = (int) (prime * result + y); result = (int) (prime * result + Double.doubleToLongBits(d)); return result; } @Override public boolean equals(Object obj) { if (this == obj) { return true; } if (obj instanceof Member) { Member other = (Member) obj; return other.x == x && other.y == y && Double.compare(d, other.d) == 0; } return false; } public static void main(String[] args) { Set<Member> test = new HashSet<Member>(); Member b = new Member(1, 2, 3); test.add(b); System.out.println(b.hashCode()); b.x = 0; System.out.println(b.hashCode()); Member first = test.iterator().next(); System.out.println(test.contains(first)); System.out.println(b.equals(first)); System.out.println(test.add(first)); } } It produces the following results: 30814 29853 false true true Because the hashCode depends of the state of the object it can no longer by retrieved properly, so the check for containment fails. The HashSet in no longer working properly. A solution would be to make Member immutable, but is that the only solution? Should all classes added to HashSets be immutable? Is there any other way to handle the situation? Regards.

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  • Java: Is there a way to efficiently insert or remove many elements from the middle of a LinkedList?

    - by allyourcode
    I was expecting to find this in Java's LinkedList, since the point of linked lists is to be able to efficiently insert (and remove) anywhere (assuming you have some kind of pointer to the location where you want to insert or remove). I'm not finding anything in the API though. Am I overlooking something? The closest thing I can find to this are the add and remove method in ListIterator. This has some limitations though. In particular, other iterators become invalid as soon as the underlying LinkedList is modified via remove, according to the API. This is born out in my tests as well; the following program results in a IllegalStateException: import java.util.*; public class RemoveFromLinkedList { public static void main(String[] args) { LinkedList<Integer> myList= new LinkedList<Integer>(); for (int i = 0; i < 10; ++i) { myList.add(i); } ListIterator<Integer> i1 = myList.listIterator(); ListIterator<Integer> i2 = myList.listIterator(); for (int i = 0; i < 3; ++i) { i1.next(); i2.next(); } System.out.println("i1.next() should be 3: " + i1.next()); i1.remove(); i1.remove(); // Exception! System.out.println("i2.next() should be 5: " + i2.next()); } } Ideally, what I'm expecting is something like this: // In my imagination only. This is the way Java actually works, afaict. // Construct two insertion/deletion points in LinkedList myLinkedList. myIterator = myLinkedList.iterator(); for (...) { myIterator.next(); } start = myIterator.clone(); for (...) { myIterator.next(); } // Later... after = myLinkedList.spliceAfter(myIterator, someOtherLinkedList); // start, myIterator, and after are still all valid; thus, I can do this: // Removes everything I just spliced in, as well as some other stuff before that. myLinkedList.remove(start, after); // Now, myIterator is invalid, but not start, nor after. C++ has something like this for its list class (template). Only iterators pointing to moved elements become invalidated, not ALL iterators.

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  • Why is Dictionary.First() so slow?

    - by Rotsor
    Not a real question because I already found out the answer, but still interesting thing. I always thought that hash table is the fastest associative container if you hash properly. However, the following code is terribly slow. It executes only about 1 million iterations and takes more than 2 minutes of time on a Core 2 CPU. The code does the following: it maintains the collection todo of items it needs to process. At each iteration it takes an item from this collection (doesn't matter which item), deletes it, processes it if it wasn't processed (possibly adding more items to process), and repeats this until there are no items to process. The culprit seems to be the Dictionary.Keys.First() operation. The question is why is it slow? Stopwatch watch = new Stopwatch(); watch.Start(); HashSet<int> processed = new HashSet<int>(); Dictionary<int, int> todo = new Dictionary<int, int>(); todo.Add(1, 1); int iterations = 0; int limit = 500000; while (todo.Count > 0) { iterations++; var key = todo.Keys.First(); var value = todo[key]; todo.Remove(key); if (!processed.Contains(key)) { processed.Add(key); // process item here if (key < limit) { todo[key + 13] = value + 1; todo[key + 7] = value + 1; } // doesn't matter much how } } Console.WriteLine("Iterations: {0}; Time: {1}.", iterations, watch.Elapsed); This results in: Iterations: 923007; Time: 00:02:09.8414388. Simply changing Dictionary to SortedDictionary yields: Iterations: 499976; Time: 00:00:00.4451514. 300 times faster while having only 2 times less iterations. The same happens in java. Used HashMap instead of Dictionary and keySet().iterator().next() instead of Keys.First().

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  • Vector Troubles in C++

    - by DistortedLojik
    I am currently working on a project that deals with a vector of objects of a People class. The program compiles and runs just fine, but when I use the debugger it dies when trying to do anything with the PersonWrangler object. I currently have 3 different classes, one for the person, a personwrangler which handles all of the people collectively, and a game class that handles the game input and output. Edit: My basic question is to understand why it is dying when it calls outputPeople. Also I would like to understand why my program works exactly as it should unless I use the debugger. The outputPeople function works the way I intended that way. Edit 2: The callstack has 3 bad calls which are: std::vector ::begin(this=0xbaadf00d) std::vector ::size(this=0xbaadf00d) PersonWrangler::outputPeople(this=0xbaadf00d) Relevant code: class Game { public: Game(); void gameLoop(); void menu(); void setStatus(bool inputStatus); bool getStatus(); PersonWrangler* hal; private: bool status; }; which calls outputPeople where it promptly dies from a baadf00d error. void Game::menu() { hal->outputPeople(); } where hal is an object of PersonWrangler type class PersonWrangler { public: PersonWrangler(int inputStartingNum); void outputPeople(); vector<Person*> peopleVector; vector<Person*>::iterator personIterator; int totalPeople; }; and the outputPeople function is defined as void PersonWrangler::outputPeople() { int totalConnections = 0; cout << " Total People:" << peopleVector.size() << endl; for (unsigned int i = 0;i < peopleVector.size();i++) { sort(peopleVector[i]->connectionsVector.begin(),peopleVector[i]->connectionsVector.end()); peopleVector[i]->connectionsVector.erase( unique (peopleVector[i]->connectionsVector.begin(),peopleVector[i]->connectionsVector.end()),peopleVector[i]->connectionsVector.end()); peopleVector[i]->outputPerson(); totalConnections+=peopleVector[i]->connectionsVector.size(); } cout << "Total connections:" << totalConnections/2 << endl; }

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  • c++ template function compiles in header but not implementation

    - by flies
    I'm trying to learn templates and I've run into this confounding error. I'm declaring some functions in a header file and I want to make a separate implementation file where the functions will be defined. Here's the code that calls the header (dum.cpp): #include <iostream> #include <vector> #include <string> #include "dumper2.h" int main() { std::vector<int> v; for (int i=0; i<10; i++) { v.push_back(i); } test(); std::string s = ", "; dumpVector(v,s); } now, here's a working header file (dumper2.h): #include <iostream> #include <string> #include <vector> void test(); template <class T> void dumpVector( std::vector<T> v,std::string sep); template <class T> void dumpVector(std::vector<T> v, std::string sep) { typename std::vector<T>::iterator vi; vi = v.begin(); std::cout << *vi; vi++; for (;vi<v.end();vi++) { std::cout << sep << *vi ; } std::cout << "\n"; return; } with implentation (dumper2.cpp): #include <iostream> #include "dumper2.h" void test() { std::cout << "!olleh dlrow\n"; } the weird thing is that if I move the code that defines dumpVector from the .h to the .cpp file, I get the following error: g++ -c dumper2.cpp -Wall -Wno-deprecated g++ dum.cpp -o dum dumper2.o -Wall -Wno-deprecated /tmp/ccKD2e3G.o: In function `main': dum.cpp:(.text+0xce): undefined reference to `void dumpVector<int>(std::vector<int, std::allocator<int> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >)' collect2: ld returned 1 exit status make: *** [dum] Error 1 So why does it work one way and not the other? Clearly the compiler can find test(), so why can't it find dumpVector?

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  • vector does not erase content correctly (infite amount run of copy asignment operator untill crash [BEX])?

    - by Gam Erix
    Well my problem is that after I want to "unload" loaded DLL's the copy assignmnent operator is called an unlimited amount of times until crash. The code from which I remove the vector data looks like this: void UnloadPlugins() { dbg(("[DBG]UnloadPlugins()")); for(std::vector<DLLInfo>::iterator it = plugins.begin(); it != plugins.end(); ++it) { plugins.erase(it); } dbg(("[DBG]UnloadPlugins()::Done")); } however "[DBG]UnloadPlugins()::Done" gets never printed. this is my copy assignmnent operator: // 2. copy assignment operator DLLInfo& operator=(const DLLInfo& that) { dbg(("[DBG]Start-DLLInfo& operator=(const DLLInfo& that)")); Instance = that.Instance;//hinstance dbg(("[DBG]DLLInfo 1")); //Identifier.assign(that.Identifier);//string dbg(("[DBG]DLLInfo 2")); IsAMX = that.IsAMX;//integer dbg(("[DBG]DLLInfo 3")); dwSupportFlags = that.dwSupportFlags;//integer dbg(("[DBG]DLLInfo 4")); Load = that.Load;//integer dbg(("[DBG]DLLInfo 5")); Unload = that.Unload;//integer dbg(("[DBG]DLLInfo 6")); Supports = that.Supports;//integer dbg(("[DBG]DLLInfo 7")); ProcessTick = that.ProcessTick;//integer dbg(("[DBG]DLLInfo 8")); AmxLoad = that.AmxLoad;//integer dbg(("[DBG]DLLInfo 9")); AmxUnload = that.AmxUnload;//integer dbg(("[DBG]DLLInfo 10")); UseDestructor = that.UseDestructor;//bool dbg(("[DBG]DLLInfo 11")); KeyboardHit = that.KeyboardHit;//integer dbg(("[DBG]End-DLLInfo& operator=(const DLLInfo& that)")); return *this; } So the log looks like: [17:50:50] [DBG]UnloadPlugins() [17:50:50] [DBG]~DLLInfo [17:50:50] [DBG]~DLLInfo::if(this->UseDestructor) passed [17:50:50] [DBG]~DLLInfo::if(this->UseDestructor)::if(this->Unload != NULL && this->IsAMX) passed [17:50:50] [DBG]~DLLInfo::end [17:50:50] [DBG]Start-DLLInfo& operator=(const DLLInfo& that) [17:50:50] [DBG]DLLInfo 1 [17:50:50] [DBG]DLLInfo 2 [17:50:50] [DBG]DLLInfo 3 [17:50:50] [DBG]DLLInfo 4 [17:50:50] [DBG]DLLInfo 5 [17:50:50] [DBG]DLLInfo 6 [17:50:50] [DBG]DLLInfo 7 [17:50:50] [DBG]DLLInfo 8 [17:50:50] [DBG]DLLInfo 9 [17:50:50] [DBG]DLLInfo 10 [17:50:50] [DBG]DLLInfo 11 [17:50:50] [DBG]End-DLLInfo& operator=(const DLLInfo& that) [17:50:50] [DBG]Start-DLLInfo& operator=(const DLLInfo& that) ... [17:50:50] [DBG]End-DLLInfo& operator=(const DLLInfo& that) ...repeat until crash What could the problem be?

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