What's the problem ??

Question

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

int main() {
char chaine[50];

scanf("%s",chaine);
printf("%s",strrev(chaine));

return 0;
}

Answer 1

strrev is a non-standard function. It's not included in the standardized C language and isn't available in the SL playground. You can implement a reverse function yourself though.