#include <stdio.h>

int main() {
  
   char myText[] = "John is the fastest kid in town";
   char myReplace[] = "pet";
   printf("%s\n", myText);
   __asm {
      cld                ;// clear direction flag
      mov ecx, 3         ;// set loop counter
      lea eax, myReplace     
      mov esi, eax       ;// set esi to address of myReplace
      lea eax, myText+20   
      mov edi, eax;      ;// set edi to address of myText
      rep movsb;
   }

  printf("%s\n", myText);
  return 0;
}