I am creating my own stack for my data structures class. For our assignment we are using the assignment to convert a real-time infix equation into a postfix equation.
I thought my program:
took input
determines if it was digit or number(operand)
prints it out
determines if input is operator (+,-,/,*)
adds to stack or prints out, depending on stack precedence
Instead it prints out the operands as expect, but I get this error when I enter an operator
.../dorun.sh line 33: 4136 Segmentation fault sh "$"
[code]
#include
using namespace std;
class DishWell{
public:
char ReturnEnd(){
return Well.back();
}
void Push(char x){
Well.push_back(x);
}
void Pop(){
Well.pop_back();
}
bool IsEmpty(){
return Well.empty();
}
private:
vector<char> Well;
};
#include <iostream>
bool Precidence(char Input, char Stack){
int InputPrecidence,StackPrecidence;
switch (Input){
case '*':
InputPrecidence = 4;
break;
case '/':
InputPrecidence = 4;
break;
case '+':
InputPrecidence = 3;
break;
case '-':
InputPrecidence = 3;
break;
case '(':
InputPrecidence = 2;
break;
default:
InputPrecidence = 0;
}
switch (Stack){
case '*':
StackPrecidence = 4;
break;
case '/':
StackPrecidence = 4;
break;
case '+':
StackPrecidence = 3;
break;
case '-':
StackPrecidence = 3;
break;
case '(':
StackPrecidence = 2;
break;
default:
StackPrecidence = 0;
}
if(InputPrecidence>StackPrecidence) return true;
else return false;
}
int main(int argc, char** argv) {
DishWell DishTray;
char Input;
bool InputFlag;
InputFlag = true;
while(InputFlag){
cin>>Input;
if((((Input>='a'&&Input<='z')||(Input>='A'&&Input<='Z'))|| (Input>='0'&&Input<='9')))//If Digit or Number
cout<<Input;
if((Input=='*'||Input=='/'||Input=='+'||Input=='-')){//if operand
if(Precidence(Input,DishTray.ReturnEnd()))
DishTray.Push(Input);
else if(!Precidence(Input,DishTray.ReturnEnd()))
cout<<Input;
}
else if(!((((Input>='a'&&Input<='z')||(Input>='A'&&Input<='Z'))|| (Input>='0'&&Input<='9')))||((Input=='*'||Input=='/'||Input=='+'||Input=='-')))//if not digit/numer or operand
InputFlag = false;
}
while(!DishTray.IsEmpty()){
cout<<DishTray.ReturnEnd();
DishTray.Pop();
}
return 0;
[code]
My code is very length, I know, but I appreciate help. Especially any times for efficency or future coding.
Thanks again
P.S. Dr. Zemoudeh, this is your student Macaire
