inverse String in c

Question

i've done a function that inverse a String(array of character) given in parameter , but it's not working , any idea why ?

I'm getting something like this : æIGt(Kt$0@

thanks you

#include <stdio.h>
#include <string.h>

char *
inverse(char *s)
{
    int i, taille = strlen(s);
    char r[taille];
    for (i = 0 ; i < taille ; i++)
    {
        r[i] = s[taille - i - 1];
    }
    r[i] = '\0';    
    return r;
}

int
main()
{    
    char s[] = "kira";
    char *r = inverse(s);

    printf("%s",r);

    return 1;
}

Answer 1

You are returning a pointer to a local variable. That variable gets destroied when the function inverse returns, so accessing the pointer after the function exits will return invalid data.

Answer 2

It's slightly hard to tell from you question, because you haven't given any outputs, but my best guess is that it's because your returning a pointer to an item on the stack, which will get over-written by the next call, in your case printf. You need to pass inverse a place to put its answer. Try this instead:

#include <stdio.h>
#include <string.h>

void inverse(char *s, char *r)
{
    int i,taille=strlen(s);


    for(i=0;i<taille;i++)
    {
        r[i]=s[taille-i-1];
    }
    r[i]='\0';
}



int main()
{

char s[] = "kira";
char r[sizeof(s)];

inverse(s, r);    

printf("%s",r);

return 1;
}