# C++ Program to Check Leap Year

A leap year is a calendar year in which an additional day is added to February month. In a leap year, the number of days in February month and the year are 29 and 366 respectively. A year that is not a leap year is called a common year. A year is said to be a leap year if

• it is divisible by 4.
• it is divisible by 4 but not divisible by 100.
• it is divisible by 4, 100 and 400.

### Example: Using conditional statements

In the below example, conditional statements are used to identify a leap year.

#include <iostream>
using namespace std;

int main() {
int year = 2019;
if (year % 400 == 0) {
cout<<year<<" is a leap year.";
} else if (year % 100 == 0) {
cout<<year<<" is not a leap year.";
} else if (year % 4 == 0) {
cout<<year<<" is a leap year.";
} else {
cout<<year<<" is not a leap year.";
}
return 0;
}


Output

2019 is not a leap year.


### Example: Using function

In the below example, a function called leapyear() is created which takes year as argument and prints whether the passed year is a leap year or not.

#include <iostream>
using namespace std;

static void leapyear(int);

static void leapyear(int year) {
if (year % 400 == 0) {
cout<<year<<" is a leap year.";
} else if (year % 100 == 0) {
cout<<year<<" is not a leap year.";
} else if (year % 4 == 0) {
cout<<year<<" is a leap year.";
} else {
cout<<year<<" is not a leap year.";
}
}
int main() {
leapyear(2019);
return 0;
}


Output

2019 is not a leap year.