#include <stdio.h>
int main()
{
  char ch;
  scanf("%c",&ch);
  ch=ch+('a'-'A')*(ch>='A'&& ch<="Z");
  A=65
  a=97
  ch=65+(97-65)*0
  65+32*1
  a=97
  ch=97+(97-65)*0
  printf("%d",ch);
  return 0;
}