#include <stdio.h> int main() { int year; printf("Enter a year: "); scanf("%d",&year); if(year%4 == 0) { if( year%100 == 0) { // year is divisible by 400, hence the year is a leap year if ( year%400 == 0) printf("%d is a leap year.", year); else printf("%d is not a leap year.", year); } else printf("%d is a leap year.", year ); } else printf("%d is not a leap year.", year); return 0; }

Enter a year: 1900 1900 is not a leap year.

A leap year is exactly divisible by 4 except for century years (years ending with 00). The century year is a leap year only if it is perfectly divisible by 400.