Problem-1

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