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  • With XSLT, how can I use this if-test with an array, when search element is returned by a template call inside the for loop?

    - by codesforcoffee
    I think this simple example might ask the question a lot more clearly. I have an input file with multiple products. There are 10 types of product (2 product IDs is fine enough for this example), but the input will have 200 products, and I only want to output the info for the first product of each type. (Output info for the lowest priced one, so the first one will be the lowest price because I sort by Price first.) So I want to read in each product, but only output the product's info if I haven't already output a product with that same ID. I couldn't figure out how to get the processID template to return a value that I need to do my if-check on, that uses parameters from inside the for-each Product loop -then properly close the if tag in the right place so it won't output the open Product tag unless it passes the if test. I know the following code does not work, but it illustrates the idea and gives me a place to start: <?xml version="1.0" encoding="utf-8"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="xml" encoding="UTF-8" indent="yes" cdata-section-elements="prod_name adv_notes"/> <xsl:template match="/"> <List> <xsl:for-each select="ProductGroup"> <xsl:sort select="ActiveProducts/Product/Rate"/> <xsl:variable name="IDarray"> <xsl:for-each select="ActiveProducts/Product"> <xsl:variable name="CurrentID"> <xsl:call-template name="processID"> <xsl:with-param name="ProductCode" select="ProductCode" /> </xsl:call-template> </xsl:variable> <xsl:if test="not(contains($IDarray, $CurrentID))"> <child elem="{@elem}"> <xsl:select value-of="$CurrentID" /> </child> <Product> <xsl:attribute name="ID"> <xsl:select value-of="$CurrentID" /> </xsl:attribute> <prod_name> <xsl:value-of select="../ProductName"/> </prod_name> <rate> <xsl:value-of select="../Rate"/> </rate> </Product> </xsl:if> </xsl:for-each> </xsl:variable> </xsl:for-each> </List> </xsl:template> <xsl:template name="processID"> <xsl:param name="ProductCode"/> <xsl:choose> <xsl:when test="starts-with($ProductCode, '515')">5</xsl:when> <xsl:when test="starts-with($ProductCode, '205')">2</xsl:when> </xsl:choose> </xsl:template> Thanks so much in advance, I know some of the awesome programmers here can help! :) -Holly An input would look like this: <ProductGroup> <ActiveProducts> <Product> <ProductCode> 5155 </ProductCode> <ProductName> House </ProductName> <Rate> 3.99 </Rate> </Product> <Product> <ProductCode> 5158 </ProductCode> <ProductName> House </ProductName> <Rate> 4.99 </Rate> </Product> </ActiveProducts> </ProductGroup> <ProductGroup> <ActiveProducts> <Product> <ProductCode> 2058 </ProductCode> <ProductName> House </ProductName> <Rate> 2.99 </Rate> </Product> <Product> <ProductCode> 2055 </ProductCode> <ProductName> House </ProductName> <Rate> 7.99 </Rate> </Product> </ActiveProducts> </ProductGroup> 200 of those with different attributes. I have the translation working, just needed to add that array and if statement somehow. Output would be this for only that simple input file:

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  • Unmanaged Struct Instance in Managed Class

    - by HeHasMoments
    Hi, I've got a fairly specific problem i've been struggling with for a couple of days. I'm using a native C++, one of the methods takes a ptr to a struct containing fixed size char arrays. e.g. struct userData { char data1[10]; char data2[10]; }; method: short AddItem(long id, userData* data); I'm trying to call to call this from Managed VC++ but I need to have an instance of userData I can keep hold of in my managed class. Can anyone help with how to achieve this? Thanks

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  • Designing an API with compile-time option to remove first parameter to most functions and use a glob

    - by tomlogic
    I'm trying to design a portable API in ANSI C89/ISO C90 to access a wireless networking device on a serial interface. The library will have multiple network layers, and various versions need to run on embedded devices as small as an 8-bit micro with 32K of code and 2K of data, on up to embedded devices with a megabyte or more of code and data. In most cases, the target processor will have a single network interface and I'll want to use a single global structure with all state information for that device. I don't want to pass a pointer to that structure through the network layers. In a few cases (e.g., device with more resources that needs to live on two networks) I will interface to multiple devices, each with their own global state, and will need to pass a pointer to that state (or an index to a state array) through the layers. I came up with two possible solutions, but neither one is particularly pretty. Keep in mind that the full driver will potentially be 20,000 lines or more, cover multiple files, and contain hundreds of functions. The first solution requires a macro that discards the first parameter for every function that needs to access the global state: // network.h typedef struct dev_t { int var; long othervar; char name[20]; } dev_t; #ifdef IF_MULTI #define foo_function( x, a, b, c) _foo_function( x, a, b, c) #define bar_function( x) _bar_function( x) #else extern dev_t DEV; #define IFACE (&DEV) #define foo_function( x, a, b, c) _foo_function( a, b, c) #define bar_function( x) _bar_function( ) #endif int bar_function( dev_t *IFACE); int foo_function( dev_t *IFACE, int a, long b, char *c); // network.c #ifndef IF_MULTI dev_t DEV; #endif int bar_function( dev_t *IFACE) { memset( IFACE, 0, sizeof *IFACE); return 0; } int foo_function( dev_t *IFACE, int a, long b, char *c) { bar_function( IFACE); IFACE->var = a; IFACE->othervar = b; strcpy( IFACE->name, c); return 0; } The second solution defines macros to use in the function declarations: // network.h typedef struct dev_t { int var; long othervar; char name[20]; } dev_t; #ifdef IF_MULTI #define DEV_PARAM_ONLY dev_t *IFACE #define DEV_PARAM DEV_PARAM_ONLY, #else extern dev_t DEV; #define IFACE (&DEV) #define DEV_PARAM_ONLY void #define DEV_PARAM #endif int bar_function( DEV_PARAM_ONLY); // I don't like the missing comma between DEV_PARAM and arg2... int foo_function( DEV_PARAM int a, long b, char *c); // network.c #ifndef IF_MULTI dev_t DEV; #endif int bar_function( DEV_PARAM_ONLY) { memset( IFACE, 0, sizeof *IFACE); return 0; } int foo_function( DEV_PARAM int a, long b, char *c) { bar_function( IFACE); IFACE->var = a; IFACE->othervar = b; strcpy( IFACE->name, c); return 0; } The C code to access either method remains the same: // multi.c - example of multiple interfaces #define IF_MULTI #include "network.h" dev_t if0, if1; int main() { foo_function( &if0, -1, 3.1415926, "public"); foo_function( &if1, 42, 3.1415926, "private"); return 0; } // single.c - example of a single interface #include "network.h" int main() { foo_function( 11, 1.0, "network"); return 0; } Is there a cleaner method that I haven't figured out? I lean toward the second since it should be easier to maintain, and it's clearer that there's some macro magic in the parameters to the function. Also, the first method requires prefixing the function names with "_" when I want to use them as function pointers. I really do want to remove the parameter in the "single interface" case to eliminate unnecessary code to push the parameter onto the stack, and to allow the function to access the first "real" parameter in a register instead of loading it from the stack. And, if at all possible, I don't want to have to maintain two separate codebases. Thoughts? Ideas? Examples of something similar in existing code? (Note that using C++ isn't an option, since some of the planned targets don't have a C++ compiler available.)

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  • Segmentation fault before return

    - by donalmg
    Hi, Why does the following code seg fault before returning: int main() { char iD[20]; memset (iD, 0, 20); char* prefix; srand (time(NULL) ); int iPrefix = rand()%1000000; sprintf(prefix, "%i", iPrefix); int len = strlen(prefix); char* staticChar = "123456789"; //set prefix into ID memcpy(iD, prefix, len); // append static value memcpy(iD+len, staticChar, 20-len); cout << "END " << endl; return 0; } At the minute, the cout will display, but I get a segmentation fault.

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  • Why does strlen not working for me?

    - by tushar
    char p[4]={'h','g','y'}; cout<<strlen(p); This code prints 3. char p[3]={'h','g','y'}; cout<<strlen(p); This prints 8. char p[]={'h','g','y'}; cout<<strlen(p); This again prints 8. Please help me as I can't figure out why three different values are printed by changing the size of the array.

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  • How to display label of unnamed drive ?

    - by iira
    I want to get the name or label of drive. I use this function : function GetVolumeLabel(DriveChar: Char): string; var NotUsed: DWORD; VolumeFlags: DWORD; VolumeInfo: array[0..MAX_PATH] of Char; VolumeSerialNumber: DWORD; Buf: array [0..MAX_PATH] of Char; begin GetVolumeInformation(PChar(DriveChar + ':\'), Buf, SizeOf(VolumeInfo), @VolumeSerialNumber, NotUsed, VolumeFlags, nil, 0); SetString(Result, Buf, StrLen(Buf)); { Set return result } Result:=AnsiUpperCase(Result) end; For example, here're my drives in Windows Explorer : Local Disk (C:) Data (D:) DVD RW Drive (E:) The output of the code : C: D: DATA E: The labels of C and E are empty. What winapi/function should I use to display the label of unnamed drive (C and E)?

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  • Does writing program using global variables is safer?

    - by ZoZo123
    I was reading about buffer, stack and heap overflows. I read this post as well. my question is like that: if I use only global variables in my code, can I say it prevents all the exploits of overflow? let's say I have this buffers in code declared in the global scope: char buf1[10]; char buf2[100]; If I send buf1 as the buffer to recv(int s, char *buf, int len,int flags); I will overwrite the data segment and may ruin the buf2 content, right? Would I be able to run a code from it because as I know it is not a code segment and data segment is not executable. Can we conclude that using Globals is the safest way?

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  • What are these values representative of in C bitwise operations?

    - by ajax81
    Hi All, I'm trying to reverse the order of bits in C (homework question, subject: bitwise operators). I found this solution, but I'm a little confused by the hex values (?) used -- 0x01 and 0x80. unsigned char reverse(unsigned char c) { int shift; unsigned char result = 0; for (shift = 0; shift < CHAR_BITS; shift++) { if (c & (0x01 << shift)) result |= (0x80 >> shift); } return result; } The book I'm working out of hasn't discussed these kinds of values, so I'm not really sure what to make of them. Can somebody shed some light on this solution? Thank you!

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  • Setting pointers to structs

    - by Bobby
    I have the following struct: struct Datastore_T { Partition_Datastores_T cmtDatastores; // bytes 0 to 499 Partition_Datastores_T cdhDatastores; // bytes 500 to 999 Partition_Datastores_T gncDatastores; // bytes 1000 to 1499 Partition_Datastores_T inpDatastores; // bytes 1500 1999 Partition_Datastores_T outDatastores; // bytes 2000 to 2499 Partition_Datastores_T tmlDatastores; // bytes 2500 to 2999 Partition_Datastores_T sm_Datastores; // bytes 3000 to 3499 }; I want to set a char* to struct of this type like so: struct Datastore_T datastores; // Elided: datastores is initialized with data here char* DatastoreStartAddr = (char*)&datastores; memset(DatastoreStartAddr, 0, 3500); The problem I have is that DatastoreStartAddr always has a value of zero when it should point to the struct that has been initialized with data. What am I doing wrong?

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  • Strange errors in Visual C++ :: 'malloc' : function does not take 1 arguments

    - by pecker
    Error 38 error C2660: 'malloc' : function does not take 1 arguments C:\VolumeRenderer\render.cpp 296 1 VolumeRenderer Error 39 error C2660: 'malloc' : function does not take 1 arguments C:\VolumeRenderer\render.cpp 412 1 VolumeRenderer Error 40 error C2660: 'malloc' : function does not take 1 arguments C:\VolumeRenderer\render.cpp 414 1 VolumeRenderer Error 41 error C2660: 'read_den' : function does not take 4 arguments C:\VolumeRenderer\render.cpp 506 1 VolumeRenderer My all malloc sections are like this: /* allocate space for the raw data */ density_size = BRAIN_XLEN * BRAIN_YLEN * BRAIN_ZLEN; density = (unsigned char*)malloc(density_size); if (density == NULL) { fprintf(stderr, "out of memory\n"); exit(1); } regarding read_den (last error) unsigned char *read_den(char *filename,int *xptr,int *yptr,int *zptr)// function prototype src_volume = read_den(src_file, &src_xlen, &src_ylen, &src_zlen);// fucntion call Is it my code or the errors that are absurd. How to rectify them?

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  • printing double in binary

    - by Happy Mittal
    In Thinking in C++ by Bruce eckel, there is a program given to print a double value in binary.(Chapter 3, page no. 189) int main(int argc, char* argv[]) { if(argc != 2) { cout << "Must provide a number" << endl; exit(1); } double d = atof(argv[1]); unsigned char* cp = reinterpret_cast<unsigned char*>(&d); for(int i = sizeof(double); i > 0 ; i -= 2) { printBinary(cp[i-1]); printBinary(cp[i]); } } Here while printing cp[i] when i=8(assuming double is of 8 bytes), wouldn't it be undefined behaviour? I mean this code doesn't work as it doesn't print cp[0].

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  • How do you map a composite id to a composite user type with Fluent NHibernate?

    - by gabe
    i'm working w/ a legacy database is set-up stupidly with an index composed of a char id column and two char columns which make up a date and time, respectively. I have created a icompositeusertype for the date and time columns to map to a single .NET DateTime property on my entity, which works by itself when not part of the id. i need to somehow use a composite id with key property mapping that includes my icompositeusertype for mapping to the two char date and time columns. Apparently w/ my version of Fluent NHibernate, CompositeIdentityPart doesn't have a CustomTypeIs() method, so i can't just do the following in my override: mapping.UseCompositeId() .WithKeyProperty(x => x.Id, CommonDatabaseFieldNames.Id) .WithKeyProperty(x => x.FileCreationDateTime) .CustomTypeIs<FileCreationDateTimeType>(); is something like this even possible w/ NHibernate let alone Fluent? I haven't been able to find anything on this.

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  • Passing operator as a parameter

    - by nacho4d
    Hi, I want to have a function that evaluates 2 bool vars (like a truth table) for example: since T | F : T then myfunc('t', 'f', ||); /*defined as: bool myfunc(char lv, char rv, ????)*/ should return true; how can I pass the third parameter? (I know is possible to pass it as a char* but then I will have to have another table to compare operator string and then do the operation which is something I would like to avoid) Is it possible to pass an operator like ^(XOR) or ||(OR) or &&(AND), etc in a function/method? Thanks in advance

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  • OpenGL texture shifted somewhat to the left when applied to a quad

    - by user308226
    I'm a bit new to OpenGL and I've been having a problem with using textures. The texture seems to load fine, but when I run the program, the texture displays shifted a couple pixels to the left, with the section cut off by the shift appearing on the right side. I don't know if the problem here is in the my TGA loader or if it's the way I'm applying the texture to the quad. Here is the loader: #include "texture.h" #include <iostream> GLubyte uncompressedheader[12] = {0,0, 2,0,0,0,0,0,0,0,0,0}; GLubyte compressedheader[12] = {0,0,10,0,0,0,0,0,0,0,0,0}; TGA::TGA() { } //Private loading function called by LoadTGA. Loads uncompressed TGA files //Returns: TRUE on success, FALSE on failure bool TGA::LoadCompressedTGA(char *filename,ifstream &texturestream) { return false; } bool TGA::LoadUncompressedTGA(char *filename,ifstream &texturestream) { cout << "G position status:" << texturestream.tellg() << endl; texturestream.read((char*)header, sizeof(header)); //read 6 bytes into the file to get the tga header width = (GLuint)header[1] * 256 + (GLuint)header[0]; //read and calculate width and save height = (GLuint)header[3] * 256 + (GLuint)header[2]; //read and calculate height and save bpp = (GLuint)header[4]; //read bpp and save cout << bpp << endl; if((width <= 0) || (height <= 0) || ((bpp != 24) && (bpp !=32))) //check to make sure the height, width, and bpp are valid { return false; } if(bpp == 24) { type = GL_RGB; } else { type = GL_RGBA; } imagesize = ((bpp/8) * width * height); //determine size in bytes of the image cout << imagesize << endl; imagedata = new GLubyte[imagesize]; //allocate memory for our imagedata variable texturestream.read((char*)imagedata,imagesize); //read according the the size of the image and save into imagedata for(GLuint cswap = 0; cswap < (GLuint)imagesize; cswap += (bpp/8)) //loop through and reverse the tga's BGR format to RGB { imagedata[cswap] ^= imagedata[cswap+2] ^= //1st Byte XOR 3rd Byte XOR 1st Byte XOR 3rd Byte imagedata[cswap] ^= imagedata[cswap+2]; } texturestream.close(); //close ifstream because we're done with it cout << "image loaded" << endl; glGenTextures(1, &texID); // Generate OpenGL texture IDs glBindTexture(GL_TEXTURE_2D, texID); // Bind Our Texture glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); // Linear Filtered glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexImage2D(GL_TEXTURE_2D, 0, type, width, height, 0, type, GL_UNSIGNED_BYTE, imagedata); delete imagedata; return true; } //Public loading function for TGA images. Opens TGA file and determines //its type, if any, then loads it and calls the appropriate function. //Returns: TRUE on success, FALSE on failure bool TGA::loadTGA(char *filename) { cout << width << endl; ifstream texturestream; texturestream.open(filename,ios::binary); texturestream.read((char*)header,sizeof(header)); //read 6 bytes into the file, its the header. //if it matches the uncompressed header's first 6 bytes, load it as uncompressed LoadUncompressedTGA(filename,texturestream); return true; } GLubyte* TGA::getImageData() { return imagedata; } GLuint& TGA::getTexID() { return texID; } And here's the quad: void Square::show() { glEnable(GL_TEXTURE_2D); glBindTexture(GL_TEXTURE_2D, texture.texID); //Move to offset glTranslatef( x, y, 0 ); //Start quad glBegin( GL_QUADS ); //Set color to white glColor4f( 1.0, 1.0, 1.0, 1.0 ); //Draw square glTexCoord2f(0.0f, 0.0f); glVertex3f( 0, 0, 0 ); glTexCoord2f(1.0f, 0.0f); glVertex3f( SQUARE_WIDTH, 0, 0 ); glTexCoord2f(1.0f, 1.0f); glVertex3f( SQUARE_WIDTH, SQUARE_HEIGHT, 0 ); glTexCoord2f(0.0f, 1.0f); glVertex3f( 0, SQUARE_HEIGHT, 0 ); //End quad glEnd(); //Reset glLoadIdentity(); }

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  • From xcode not able to execute DISTINCT keyword for sqlite

    - by mac
    -(void) readProductsFromDatabase { // Setup the database object sqlite3 *database; // Init the animals Array products = [[NSMutableArray alloc] init]; // Open the database from the users filessytem if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) { NSLog(@"db opened"); // Setup the SQL Statement and compile it for faster access const char *sqlStatement = "SELECT DISTINCT productname FROM iphone "; sqlite3_stmt *compiledStatement; if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) { // Loop through the results and add them to the feeds array while(sqlite3_step(compiledStatement) == SQLITE_ROW) { NSLog(@"inside sqlite3 prepare"); // Read the data from the result row NSString *aName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 2)]; } } // Release the compiled statement from memory sqlite3_finalize(compiledStatement); } sqlite3_close(database); } My problem is const char *sqlStatement = "SELECT DISTINCT productname FROM iphone "; This line not executing ,i am using sqlite3, thanks in advance,

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  • How can a FILE* (pointer to a struct) be tested (if == NULL)?

    - by m4design
    I was playing around with C, anyways I was thinking how can file pointer (which points to a struct type), be tested if NULL as for instant: FILE *cfPtr; if ( ( cfPtr = fopen( "file.dat", "w" ) ) == NULL ) I tried to do that myself, but an error occurs. struct foo{ int x; }; struct foo bar = {0}; if (bar == NULL) puts("Yay\n"); else puts("Nay"); error C2088: '==' : illegal for struct Here's the FILE deceleration in the stdio.h file: struct _iobuf { char *_ptr; int _cnt; char *_base; int _flag; int _file; int _charbuf; int _bufsiz; char *_tmpfname; }; typedef struct _iobuf FILE;

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  • Alternates to C++ Reference/Pointer Syntax

    - by Jon Purdy
    What languages other than C and C++ have explicit reference and pointer type qualifiers? People seem to be easily confused by the right-to-left reading order of types, where char*& is "a reference to a pointer to a character", or a "character-pointer reference"; do any languages with explicit references make use of a left-to-right reading order, such as &*char/ref ptr char? I'm working on a little language project, and legibility is one of my key concerns. It seems to me that this is one of those questions to which it's easy for a person but hard for a search engine to provide an answer. Thanks in advance!

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  • C++: conjunction of binds?

    - by Helltone
    Suppose the following two functions: #include <iostream> #include <cstdlib> // atoi #include <cstring> // strcmp #include <boost/bind.hpp> bool match1(const char* a, const char* b) { return (strcmp(a, b) == 0); } bool match2(int a, const char* b) { return (atoi(b) == a); } Each of these functions takes two arguments, but can be transformed into a callable object that takes only one argument by using (std/boost)bind. Something along the lines of: boost::bind(match1, "a test"); boost::bind(match2, 42); I want to be able to obtain, from two functions like these that take one argument and return bool, a callable object that takes two arguments and returns the && of the bools. The type of the arguments is arbitrary. Something like an operator&& for functions that return bool.

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  • Basic help needed with pointers

    - by sbsp
    Hi, i asked some time ago on an account i cant remember how to manipulate basic pointers and someone gave me a really good demo for example char *ptr = hello (hello = a char array) so now *ptr is pointing at h ptr++ = moves the ptr to point at the next element, to get its value i do *ptr and that gives me e ok so far i hope :D but now i need to manipulate a char **ptr and was wondering how i do this in a way that mimmicks the effects of a 2d array? some basic tips would be much appreciated as i need to do an assignment that has a **ptr to immitate a 2d array and without knowing how it does this first means i cant even solve it on paper (for example, how do you dereference a **ptr, how do you get [x][y] values etc) thanks

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  • Alternatives to C++ Reference/Pointer Syntax

    - by Jon Purdy
    What languages other than C and C++ have explicit reference and pointer type qualifiers? People seem to be easily confused by the right-to-left reading order of types, where char*& is "a reference to a pointer to a character", or a "character-pointer reference"; do any languages with explicit references make use of a left-to-right reading order, such as &*char/ref ptr char? I'm working on a little language project, and legibility is one of my key concerns. It seems to me that this is one of those questions to which it's easy for a person but hard for a search engine to provide an answer. Thanks in advance!

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  • regular expression on replace method of js not working

    - by user950146
    why this is not working var value = arr[row][col].replace(new RegExp('"', 'g'),'""'); Error : Webpage error details User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; InfoPath.2; Tablet PC 2.0) Timestamp: Tue, 10 Apr 2012 11:22:01 UTC Message: Object doesn't support this property or method Line: 1041 Char: 25 Code: 0 URI: http://example.com/? Message: Object doesn't support this property or method Line: 1041 Char: 25 Code: 0 URI: http://example.com/? Message: Object doesn't support this property or method Line: 1041 Char: 25 Code: 0 URI: http://example.com/? Note: : Error copied directly from debugger of IE8

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  • Basic help needed with pointers (double indirection)

    - by sbsp
    Hi, i asked some time ago on an account i cant remember how to manipulate basic pointers and someone gave me a really good demo for example char *ptr = "hello" (hello = a char array) so now *ptr is pointing at h ptr++ = moves the ptr to point at the next element, to get its value i do *ptr and that gives me e ok so far i hope :D but now i need to manipulate a char **ptr and was wondering how I do this in a way that mimmicks the effects of a 2d array? some basic tips would be much appreciated as I need to do an assignment that has a **ptr to imitate a 2d array and without knowing how it does this first means I cant even solve it on paper (for example, how do you dereference a **ptr, how do you get [x][y] values etc) thanks

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  • Simple 'database' in c++

    - by DevAno1
    Hello. My task was to create pseudodatabase in c++. There are 3 tables given, that store name(char*), age(int), and sex (bool). Write a program allowing to : - add new data to the tables - show all records - sort tables with criteria : - name increasing/decreasing - age increasing/decreasing - sex Using function templates is a must. Also size of arrays must be variable, depending on the amount of records. I have some code but there are still problems there. Here's what I have: Function tabSize() for returning size of array. But currently it returns size of pointer I guess : #include <iostream> using namespace std; template<typename TYPE> int tabSize(TYPE *T) { int size = 0; size = sizeof(T) / sizeof(T[0]); return size; } How to make it return size of array, not its pointer ? Next the most important : add() for adding new elements. Inside first I get the size of array (but hence it returns value of pointer, and not size it's of no use now :/). Then I think I must check if TYPE of data is char. Or am I wrong ? // add(newElement, table) template<typename TYPE> TYPE add(TYPE L, TYPE *T) { int s = tabSize(T); //here check if TYPE = char. If yes, get the length of the new name int len = 0; while (L[len] != '\0') { len++; } //current length of table int tabLen = 0; while (T[tabLen] != '\0') { tabLen++; } //if TYPE is char //if current length of table + length of new element exceeds table size create new table if(len + tabLen > s) { int newLen = len + tabLen; TYPE newTab = new [newLen]; for(int j=0; j < newLen; j++ ){ if(j == tabLen -1){ for(int k = 0; k < len; k++){ newTab[k] = } } else { newTab[j] = T[j]; } } } //else check if tabLen + 1 is greater than s. If yes enlarge table by 1. } Am I thinking correct here ? Last functions show() is correct I guess : template<typename TYPE> TYPE show(TYPE *L) { int len = 0; while (L[len] == '\0') { len++; } for(int i=0; i<len; i++) { cout << L[i] << endl; } } and problem with sort() is as follows : Ho can I influence if sorting is decreasing or increasing ? I'm using bubble sort here. template<typename TYPE> TYPE sort(TYPE *L, int sort) { int s = tabSize(L); int len = 0; while (L[len] == '\0') { len++; } //add control increasing/decreasing sort int i,j; for(i=0;i<len;i++) { for(j=0;j<i;j++) { if(L[i]>L[j]) { int temp=L[i]; L[i]=L[j]; L[j]=temp; } } } } And main function to run it : int main() { int sort=0; //0 increasing, 1 decreasing char * name[100]; int age[10]; bool sex[10]; char c[] = "Tom"; name[0] = "John"; name[1] = "Mike"; cout << add(c, name) << endl; system("pause"); return 0; }

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  • c++: use a #define in printf?

    - by John
    I was wanting to use a constant of some kind for the application ID (so I can use it in printf). I had this: #define _APPID_ "Hello World!" And then the simple printf, calling it into %s (string). It put this out: simple.cpp:32: error: cannot convert ‘_IO_FILE*’ to ‘const char*’ for argument ‘1’ to ‘int printf(const char*, ...)’ What would I use to define the application ID to use in printf? I tried: static const char _APPID_[] = "Hello World"` but it didn't work, same error I think.

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  • Method sscanf() ambiguous behavior

    - by Carmen Cojocaru
    I am trying to understand how sscanf() works. I ran some examples from this page: http://docs.roxen.com/pike/7.0/tutorial/strings/sscanf.xml and they don't work on my platform. I can't understand why. For instance: "sscanf("4711bar", "%d%s", a, b);" makes the program exit with an error... Here is one of the examples that work: "sscanf("foo", "f%s", a);". Does anybody know why? Do they work on your platforms? Thank you. This is my code: int main(void){ char *b = (char*)malloc(sizeof(char)*100); int a = 0; sscanf("4711bar", "%d%s", a, b); printf("%d", a); printf("%s", b); }

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