#include <stdio.h>

main()

{

char c;

printf("please input a string:");

while((c=getchar())!='\n')

{

  if(c>='A'&&c<='W'||c>='a'&&c<='w') c=c+3;

  else if(c>='X'&&c<='Z'||c>='x'&&c<='z') c=(c+3)-26;

  printf("%c",c);

}

printf("\n");