#include <stdio.h> #include <string.h> int main() { int t; int n; char *ptr = NULL; char *s = NULL; scanf("%d", &t); for (int i = 0; i < t; i++) { scanf("%d", &n); ptr = malloc(n + 1); s = malloc(n + 1); scanf("%s", ptr); int len = strlen(ptr); for (int index = len - 1; index >= 0; index--) { s[len - index - 1] = ptr[index]; } printf("%s\n", s); memset(ptr, 0, n + 1); memset(s, 0, n + 1); free(ptr); free(s); ptr = NULL; s = NULL; } }