#include<stdio.h>
int main ()
{
int year,a,b,c;
scanf("%d",&year);
a=year%4;
b=year%100;
c=year%400;
if(a==0)
{
if(b==0)
{
if(c==0)
printf("闰年\n");
else
printf("不是闰年\n");
}
else
printf("不是闰年\n");
}
else
printf("不是闰年\n");
return 0;
}