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infinite loop with <stack> header

m0j1 (4)
hi , this is my first post here . I've wrote a program that uses <stack> header and I need to use a while operation in my code . the problem is when I use stack header operations like stack.pop() in the while it gives me errors when I run the program(it compiles without errors) . for example the code below gives me error :
"Debug assertion failed!
Expression: deque empty before pop"
the code that gives me this error is:
while(true){
stack.pop();
break;
}
anyone knows what's the problem .
thanks
m0j1 (4)
here's the complete code:

#include <iostream>
using std::cout;
using std::cin;
using std::endl;
#include <string>
#include <stack>
using namespace std;
#include <cctype>
#include <ctype.h>


//--------------------------------------------------------
//--------------------------------------------------------
char Action[6][6];
char Action2[6][6];
//----Grammer Rules
char arr1[]={'S','E','E'};
char arr2[]={'E','(','q'};
int Numfunc(char a){
int c;
switch(a){
case '0':
c=0;break;
case '1':
c=1;break;
case '2':
c=2;break;
case '3':
c=3;break;
case '4':
c=4;break;
case '5':
c=5;break;
}
return c;
}
char actionfunc(char a,char b){
int c;
int d;
switch(b){
case 'q':
c=0;break;
case '(':
c=1;break;
case ')':
c=2;break;
case '$':
c=3;break;
case 'S':
c=4;break;
case 'E':
c=5;break;
}
switch(a){
case '0':
d=0;break;
case '1':
d=1;break;
case '2':
d=2;break;
case '3':
d=3;break;
case '4':
d=4;break;
case '5':
d=5;break;
}

return Action[d][c];
}
char actionfunc2(char a,char b){
int d;
int c;
switch(b){
case 'q':
c=0;break;
case '(':
c=1;break;
case ')':
c=2;break;
case '$':
c=3;break;
case 'S':
c=4;break;
case 'E':
c=5;break;
}
switch(a){
case '0':
d=0;break;
case '1':
d=1;break;
case '2':
d=2;break;
case '3':
d=3;break;
case '4':
d=4;break;
case '5':
d=5;break;
}
return Action2[d][c];
}

int main ()
{
int k=0;
stack<char> mystack;
stack<char> stack;
//-----<initializing parse table Action>---
Action[0][0]='S';
Action[0][1]='S';
Action[0][2]='E';
Action[0][3]='E';
Action[0][4]='E';
Action[0][5]='S';
Action[1][0]='E';
Action[1][1]='E';
Action[1][2]='E';
Action[1][3]='A';
Action[1][4]='E';
Action[1][5]='E';
Action[2][0]='S';
Action[2][1]='S';
Action[2][2]='E';
Action[2][3]='E';
Action[2][4]='E';
Action[2][5]='S';
Action[3][0]='E';
Action[3][1]='E';
Action[3][2]='R';
Action[3][3]='R';
Action[3][4]='E';
Action[3][5]='E';
Action[4][0]='E';
Action[4][1]='E';
Action[4][2]='S';
Action[4][3]='E';
Action[4][4]='E';
Action[4][5]='E';
Action[5][0]='E';
Action[5][1]='E';
Action[5][2]='R';
Action[5][3]='R';
Action[5][4]='E';
Action[5][5]='E';
//-----</initializing parse table Action>--
//-----<initializing parse table Action2>--
for(int i=0;i<6;i++){
for(int j=0;j<6;j++){
Action2[i][j]='0';
}
}
Action2[0][0]='3';
Action2[0][1]='2';
Action2[0][5]='1';
Action2[2][0]='3';
Action2[2][1]='2';
Action2[2][5]='4';
Action2[3][2]='2';
Action2[3][3]='2';
Action2[4][2]='5';
Action2[5][2]='1';
Action2[5][3]='1';
//-----</initializeing parse table Action2>
char str[500];
mystack.push('$');
cout<<"inter your lexeme: ";
cin>>str;
while(str[k]!=';'){
mystack.push(str[k]);
k++;
}
cout<<"Popping out elements...";
while(!mystack.empty()){
cout<<" "<<mystack.top();
mystack.pop();
}
cout<<endl;
//-------------------
//-------------------
stack.push('$');
stack.push('0');
while(true){
stack.push(mystack.top());
mystack.pop();
break;
char var1=stack.top();//)
stack.pop();
char var2=stack.top();//0
stack.push(var1);
//-----Shift condition------
if(actionfunc(var2,var1)=='S'){
cout<<"Shift Condition"<<endl;
char Num=actionfunc2(var2,var1);//2
stack.push(Num);
break;
}
//----Reduce condition------
else if(actionfunc(var2,var1)=='R'){
mystack.push(var1);
char Num2=actionfunc2(var2,var1);
while(stack.top()!=arr2[Numfunc(Num2)]){
stack.pop();
}
stack.pop();
stack.push(arr1[Numfunc(Num2)]);
//------
var1=stack.top();
stack.pop();
var2=stack.top();
stack.push(var1);
Num2=actionfunc2(var2,var1);
stack.push(Num2);
}
//----Error condition-------
else if(actionfunc(var2,var1)=='E'){
cout<<"Error";
break;
}
//----Accept condition------
else if(actionfunc(var2,var1)=='A'){
cout<<"lexeme is correct";
break;
}
//---Else-------------------
}

return 0;
}
//-----------------------
//-----------------------
m0j1 (4)
and when I run the complete code it gives me no error in the compilation but gives me another error in the run :
"Debug Assertion Failed!
Program:f:\C++\test5\test4\Debug\test4.exe
File:j\program files\microsoft visual studio 9.0\vc\include\deque
Line: 202
Expression: ("_Myoff + _Off <= ((_Mydeque*)(this->Getmycont()))->_Myoff+((_Mydeque*)(this->_Getmycont()))->_Mysize&&_Myoff+ _Off >= ((_Mydeque*)(this->_Getmycont()))-> _Myoff",0)
kempofighter (1183)
Here it is formatted. Please use code tags in the future and ensure that what you copy and paste is properly formatted.

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#include <iostream>
using std::cout;
using std::cin;
using std::endl;
#include <string>
#include <stack>
using namespace std;
#include <cctype>
#include <ctype.h>


//--------------------------------------------------------
//--------------------------------------------------------
char Action[6][6];
char Action2[6][6];
//----Grammer Rules
char arr1[]={'S','E','E'};
char arr2[]={'E','(','q'};
int Numfunc(char a){
	int c;
	switch(a){
case '0':
	c=0;break;
case '1':
	c=1;break;
case '2':
	c=2;break;
case '3':
	c=3;break;
case '4':
	c=4;break;
case '5':
	c=5;break;
	}
	return c;
}
char actionfunc(char a,char b){
	int c;
	int d;
	switch(b){
case 'q':
	c=0;break;
case '(':
	c=1;break;
case ')':
	c=2;break;
case '$':
	c=3;break;
case 'S':
	c=4;break;
case 'E':
	c=5;break;
	}
	switch(a){
case '0':
	d=0;break;
case '1':
	d=1;break;
case '2':
	d=2;break;
case '3':
	d=3;break;
case '4':
	d=4;break;
case '5':
	d=5;break;
	}

	return Action[d][c];
}
char actionfunc2(char a,char b){
	int d;
	int c;
	switch(b){
case 'q':
	c=0;break;
case '(':
	c=1;break;
case ')':
	c=2;break;
case '$':
	c=3;break;
case 'S':
	c=4;break;
case 'E':
	c=5;break;
	}
	switch(a){
case '0':
	d=0;break;
case '1':
	d=1;break;
case '2':
	d=2;break;
case '3':
	d=3;break;
case '4':
	d=4;break;
case '5':
	d=5;break;
	}
	return Action2[d][c];
}

int main ()
{
	int k=0;
	stack<char> mystack;
	stack<char> stack;
	//-----<initializing parse table Action>---
	Action[0][0]='S';
	Action[0][1]='S';
	Action[0][2]='E';
	Action[0][3]='E';
	Action[0][4]='E';
	Action[0][5]='S';
	Action[1][0]='E';
	Action[1][1]='E';
	Action[1][2]='E';
	Action[1][3]='A';
	Action[1][4]='E';
	Action[1][5]='E';
	Action[2][0]='S';
	Action[2][1]='S';
	Action[2][2]='E';
	Action[2][3]='E';
	Action[2][4]='E';
	Action[2][5]='S';
	Action[3][0]='E';
	Action[3][1]='E';
	Action[3][2]='R';
	Action[3][3]='R';
	Action[3][4]='E';
	Action[3][5]='E';
	Action[4][0]='E';
	Action[4][1]='E';
	Action[4][2]='S';
	Action[4][3]='E';
	Action[4][4]='E';
	Action[4][5]='E';
	Action[5][0]='E';
	Action[5][1]='E';
	Action[5][2]='R';
	Action[5][3]='R';
	Action[5][4]='E';
	Action[5][5]='E';
	//-----</initializing parse table Action>--
	//-----<initializing parse table Action2>--
	for(int i=0;i<6;i++){
		for(int j=0;j<6;j++){
			Action2[i][j]='0';
		}
	}
	Action2[0][0]='3';
	Action2[0][1]='2';
	Action2[0][5]='1';
	Action2[2][0]='3';
	Action2[2][1]='2';
	Action2[2][5]='4';
	Action2[3][2]='2';
	Action2[3][3]='2';
	Action2[4][2]='5';
	Action2[5][2]='1';
	Action2[5][3]='1';
	//-----</initializeing parse table Action2>
	char str[500];
	mystack.push('$');
	cout<<"inter your lexeme: ";
	cin>>str;
	while(str[k]!=';'){
		mystack.push(str[k]);
		k++;
	}
	cout<<"Popping out elements...";
	while(!mystack.empty()){
		cout<<" "<<mystack.top();
		mystack.pop();
	}
	cout<<endl;
	//-------------------
	//-------------------
	stack.push('$');
	stack.push('0');
	while(true){
		stack.push(mystack.top());
		mystack.pop();
		break;
		char var1=stack.top();//)
		stack.pop();
		char var2=stack.top();//0
		stack.push(var1);
		//-----Shift condition------
		if(actionfunc(var2,var1)=='S'){
			cout<<"Shift Condition"<<endl;
			char Num=actionfunc2(var2,var1);//2
			stack.push(Num);
			break;
		}
		//----Reduce condition------
		else if(actionfunc(var2,var1)=='R'){
			mystack.push(var1);
			char Num2=actionfunc2(var2,var1);
			while(stack.top()!=arr2[Numfunc(Num2)]){
				stack.pop();
			}
			stack.pop();
			stack.push(arr1[Numfunc(Num2)]);
			//------
			var1=stack.top();
			stack.pop();
			var2=stack.top();
			stack.push(var1);
			Num2=actionfunc2(var2,var1);
			stack.push(Num2);
		}
		//----Error condition-------
		else if(actionfunc(var2,var1)=='E'){
			cout<<"Error";
			break;
		}
		//----Accept condition------
		else if(actionfunc(var2,var1)=='A'){
			cout<<"lexeme is correct";
			break;
		}
		//---Else-------------------
	}

	return 0;
}
kempofighter (1183)
Here is the first question that the program asked.
inter your lexeme: hello

I entered hello. I have no idea what a lexeme is so I don't have the slightest clue what to enter. So I just entered hello. The following while loop crashes because you are searching for a ; that obviously does not exist within the string. What are you trying to do here and how do you know that the user will enter a ';'?
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char str[500];
	mystack.push('$');
	cout<<"inter your lexeme: ";
	cin>>str;
	while(str[k]!=';'){
		mystack.push(str[k]);
		k++;
	}
kempofighter (1183)
Look at line 185. Now why would you call the top member function on a stack (mystack) that you just finished emptying? What do you think will happen when you call top on an empty stack object?
Galik (2254)
Line 185: stack.push(mystack.top());

There is nothing on mystack because you just emptied it. Then you try to put its top element onto another stack.
m0j1 (4)
yeah , thank all u guys . all the errors was because I wanted to locate the top of a stack that was already was empty !
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