#include <stdio.h>
void main()
{
  int year,leap;
  scanf("%d",&year);
  if (year%4==0)
    {
      if (year%100==0)
         {
            if (year%400==0)
                leap=1;
            else leap=0;
         }
     else
         leap=1;
    }
  else
      leap=0;
if (leap)
    printf("%d is",year);
else
    printf("%d is not",year);
  printf("a leap year.\n");