1#include <stdio.h>
 2#include <stdlib.h>
 3#include <string.h>
 4#include "assertions.h"
 5
 6void reverse(char* input){
 7  char *start = input, *end, tmp;
 8
 9  end = &input[strlen(input)-1];
10
11  while(start != end){
12    tmp = *end;
13    *end = *start;
14    *start = tmp;
15    ++start;
16    if(start == end) break;
17    --end;
18  }
19}
20