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.

## Example: Java Program to Check a Leap Year

```
public class Main {
public static void main(String[] args) {
// year to be checked
int year = 1900;
boolean leap = false;
// if the year is divided by 4
if (year % 4 == 0) {
// if the year is century
if (year % 100 == 0) {
// if year is divided by 400
// then it is a leap year
if (year % 400 == 0)
leap = true;
else
leap = false;
}
// if the year is not century
else
leap = true;
}
else
leap = false;
if (leap)
System.out.println(year + " is a leap year.");
else
System.out.println(year + " is not a leap year.");
}
}
```

**Output**

1900 is not a leap year.

In the above example, we are checking if the year `1900`

is a leap year or not. Since `1900`

is a century year (ending with 00), it should be divisible by both **4** and **400** to be a leap year.

However, `1900`

is not divisible by 400. Hence, it is not a leap year.

Now, let's change the year to `2012`

. The output will be

2012 is a leap year.

Here, `2012`

is not a century year. Hence, to be a leap year, it needs to be divisible by only **4**.

Since `2012`

is divisible by 4, it is a leap year.