Thread: code won't compile

can anyone tell me where the errors are to get this thing to compile?

Code:

#include <stdio.h> 
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <ctype.h>
#define MAXSIZE 50                                        

typedef struct {
   char elements[MAXSIZE];
   int count;
} Stack;

void initialize(Stack *stackPtr); 
int isEmpty(Stack *stackPtr); 
void push(Stack *stackPtr, int x); 
void pop(Stack *stackPtr, int * x);  

int main()
{
   char PostfixExpression[MAXSIZE + 1];
   int LeftOperand, RightOperand;
   int Result;
   int i;
   char c;
   char s[MAXSIZE];
   int howlong;
   Stack EvaluateStack;

   initialize(&EvaluateStack);

   printf("Enter the postfix expression: ");
   fgets(PostfixExpression, sizeof(PostfixExpression), stdin);

   howlong = strlen(PostfixExpression);

   for(i = 0; i < howlong; i++)
   {
        c = PostfixExpression[i];
        s[0] = c;
        s[1] = '\0';

        PostfixExpression[i] = c;

        if(isdigit(c))
        {
           push(&EvaluateStack, (int)atof(s));
        }
        else if(c == '+' || c == '-' || c == '*' || c == '/') 
        {
          pop(&EvaluateStack, &RightOperand);
          pop(&EvaluateStack, &LeftOperand);
        }
        if(c == '+')
         { Result = (LeftOperand + RightOperand);
           push(&EvaluateStack, &Result);
         }
        else if(c == '-')
         {
           Result = (LeftOperand - RightOperand);
           push(&EvaluateStack, &Result);
         }
        else if(c == '*')
         {  
           Result = (LeftOperand * RightOperand);
           push(&EvaluateStack, &Result);
         }
        else
         {
           Result = (LeftOperand / RightOperand);
           push(&EvaluateStack, &Result);
         }
            
           
        }
   }
      
   pop(&EvaluateStack, &Result);
   printf("The value of the expression is: %d.\n", Result);

   return 0;
}                              

void initialize(Stack *stackPtr)
{
     stackPtr->count = 0;
} 

int isEmpty(Stack *stackPtr)
{
     if(stackPtr->count == 0)
	    return 1;
	 else
        return 0;
}

int isFull(Stack *stackPtr)
{
     if(stackPtr->count == 50)
       return 1;
     else
       return 0;
} 

void push(Stack *stackPtr, int x)
{
     if(stackPtr->count == MAXSIZE)
	 {
       printf("The stack is full, aborting...\n");
       return;
       }
       else
       {
          stackPtr->elements[stackPtr->count] = x;
          stackPtr->count++;
       }
}

void pop(Stack *stackPtr, int *x)
{
      if(stackPtr->count == 0)
      {
         printf("The stack is empty, cannot delete.\n");
         exit(0);
      }
	else
	{
	   stackPtr->count--;
	   *x = stackPtr->elements[stackPtr->count];
	}
	
        return;
}

Here are the compile errors I get but I can't figure out what is wrong on these lines:

Code:

In function `main':
61: warning: passing arg 2 of `push' makes integer from pointer without a cast
66: warning: passing arg 2 of `push' makes integer from pointer without a cast
71: warning: passing arg 2 of `push' makes integer from pointer without a cast
76: warning: passing arg 2 of `push' makes integer from pointer without a cast
At top level:
83: error: parse error before '&' token
83: error: conflicting types for 'pop'
22: error: previous declaration of 'pop' was here
83: error: conflicting types for 'pop'
22: error: previous declaration of 'pop' was here
83: warning: data definition has no type or storage class
84: error: parse error before string constant
84: error: conflicting types for 'printf'
84: note: a parameter list with an ellipsis can't match an empty parameter name list declaration
84: error: conflicting types for 'printf'
84: note: a parameter list with an ellipsis can't match an empty parameter name list declaration
84: warning: data definition has no type or storage class
125: error: conflicting types for 'pop'
83: error: previous declaration of 'pop' was here
125: error: conflicting types for 'pop'
83: error: previous declaration of 'pop' was here

no idea what compielr are you using?

On line 15 you define push as taking a pointer to a stack and an integer value. On lines 55,60,65 and 70 you pass two pointers to the function.

This is the cause of the warning: passing arg 2 of `push' makes integer from pointer without a cast message.

On line 73 you have a closing brace which doesn't match up. It closes the main function, which means the lines 74 - 79 become syntax errors.

Remove that brace and the code compiles (it does on MSVS 2003 anyway), but it craps out if you try to enter any expresson including an operator. I.E "12345" works fine (it just returns 0 as the result) but entering 12+ crashes the program.