### Python 3 program to check if a year is leap year or not :

To check if a year is leap year or not, we need to check* if it is divisible by 4 or not*. A year is leap year *if it is divisible by 4 and for century years, if it also divisible by 400*. Following algorithm we are using in the example program :

### Steps to check if a year is leap year or not :

1. Check if it is *divisible by 4*. If not than it is not a leap year.

2. If divisible by *4*, check if it is divisible by *100*. If not , *it is not a century year, so it is a leap year.*

3. If divisible by *100*, check if it is divisible by *400 or not*. If yes it is a leap year, else not.

List of leap years from *1900* to *2020* are : *1904, 1908, 1912, 1916, 1920, 1924, 1928, 1932, 1936, 1940, 1944, 1948, 1952, 1956, 1960, 1964, 1968, 1972, 1976, 1980, 1984, 1988, 1992, 1996, 2000, 2004, 2008, 2012, 2016, 2020* . You can verify with the following example :

### Program :

def printLeapYear(): print("Inpur Year is a Leap Year") def printNotLeapYear(): print("Inpur Year is not a Leap Year") input_year = int(input("Enter a Year : ")) if input_year % 4 == 0: if input_year % 100 == 0 : if input_year % 400 == 0 : printLeapYear() else : printNotLeapYear() else : printLeapYear() else : printNotLeapYear()

### Sample Output :

Enter a Year : 2000 Inpur Year is a Leap Year Enter a Year : 2001 Inpur Year is not a Leap Year