postfix evaluation

maha 5aled (2)
Hi, i'am trying to read postfix expression from txt file and evaluate it
the input is 10 5 * ,the output should be 50, but it reads only 10 and 5, where's the error?
here's my code
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#include <iostream>
 #include <iomanip>
 #include <fstream>
 #include<stdio.h>
 #include<ctype.h>
 #include<stdlib.h>
 using namespace std;
 #define SIZE 40
 int stack[SIZE];
 int top=-1;
 
void push(int n)
 {
 if(top==SIZE-1)
 {
 printf("Stack is full\n");
  system("pause");
 return;
 }
 else
 {
 top=top+1;
 stack[top]=n;
 printf("Pushed element is %d\n",n);
  system("pause");
 }
 }
 
int pop()
 {
 int n;
 if(top==-1)
 {
 printf("Stack is empty\n");
  system("pause");
 return 0;
 }
 else
 {
 n=stack[top];
 top=top-1;

 return(n);
 }
 }
 



int main() 
{
 
int str[50],ch;

 int i=0;
 int n,op1,op2;

 ifstream inFile;
 ch=str[i];

 inFile.open("D:\\me.txt");
 if (!inFile) 
{
 printf( "Unable to open file");
 system("pause");
 exit(1); // terminate with error
 }

 while (inFile >> ch) 
{
 if(ch==43 || ch==45 || ch==47 || ch==42 || ch==94 || ch==37 )
 {

	 op1=pop();
	 op2=pop();
	 if (op1<op2)
	 {
	 n=op1;
	 op1=op2;
	 op2=n;
	 }
	 switch(ch)
	 {
	 case 43:
	 n=op1+op2; break;
	 case 45:
	 n=op1-op2;break;
	 case 42:
	 n=op1*op2;break;
	 case 47:
	 n=op1/op2;break;
	 case 37:
	 n=op1%op2;break;
	 case 94:
	 n=op1^op2;break;
	
 
	 default:
	 {
	 printf("The operator is not identified\n");
	 system("pause");
	 exit(0);break;
	 }
	 }
	 printf("n=%d\n",n);
	 push(n);
	 system("pause");


 }
	 else
	 {
	 n=ch;
	 push(n);
	 }
 ch=str[++i];
 }
inFile.close();
 printf("The value of the arithmetic expression is=%d\n",pop());
 system("pause");
 return 0;
 }

bradw (34)
The variable str is not doing you anything as far as I can tell.

Are you sure that when you extract from a stream in to an integer that it will accept any ANSI character? (i.e., reading a [non-alphanumeric] character in to an integer probably fails the stream)

Case 94 probably does not do what you expect.

What kind of output are you getting?

maha 5aled (2)
he only pushes 10 & 5 into stack, and gives final evaluation as 5 !!
the problem he can't read operators neither their ascii ??
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