#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[]) {
	int year = atoi(argv[1]);
	int leap;
	if ((year % 4) != 0)
		leap = 0;
	else if ((year % 100) != 0)
		leap = 1;
	else if ((year % 400) != 0)
		leap = 0;
	else 
		leap = 1;
	if (leap == 1)
		printf("%d is a leap year.\n", year);
	else if (leap == 0)
		printf("%d is not a leap year.\n", year);
	return 0;
}