Question

I have been trying to implement a stack on dev c with c , this is my code

#include <stdio.h>
#include <stdlib.h>
#define stackinitsize 100
#define stackincrement 10

typedef struct {

    char *base;
    char *top;
    int stacksize;

}sqstack,*s;

Status initstack(sqstack &s)
{
    s.base=(char *)malloc(stackinitsize*sizeof(char));   
    if(!s.base) exit(OVERFLOW);

    s.top=s.base;  
    s.stacksize=stackinitsize;

    return OK; 
}

void push(sqstack &s,char e)
{
    if ((s.top-s.base)>=s.stacksize){

        s.base=(char *)realloc(s.base,(s.stacksize+stackincrement)*sizeof(char));
        if(!s.base) exit (OVERFLOW);
        s.top=s.base+s.stacksize;
        s.stacksize+=stackincrement;
   }

   *s.top++=e;
}

int main(int argc, char *argv[])
{
    char e;

    system("PAUSE");    
    return 0;
}

but it keeps on saying

error: syntax error before "s"
error: syntax error before '&' token    

but when I put it and compile it on codeblocks it says

error: expected ';', ',' or ')' before '&' token

Does someone have an idea?

Answer 1

You appear to be using passing by reference which is a C++ feature, not C.

You cannot use & in declaration in C, when you want to declare that a pointer is passed you use * (same goes for the push function):

Status initstack(sqstack * s)
{
    s->base=(char *)malloc(stackinitsize*sizeof(char));   
    if(!s->base) exit(OVERFLOW);
    s->top=s->base;  
    s->stacksize=stackinitsize;
    return OK; 
}

Note, however, that unlike C++ pass-by-reference, you cannot change the argument passed to the function outside of the function by assignment to s, only to dereference it.