01  #include<stdio.h>
02  #include<string.h>
03  
04  int main()
05  {
06  char str[50]="hey friend's";
07  
08  printf("Original String : %s",str);
09  strrev(str);
10  printf("nString after strrev : %s",str);
11  
12  return 0;
13  }

 OUTPUT :
 
 Original String : hey friend's
 
 String after strrev : s'dneirf yeh