Leap Year Program in Python

In this post, we will learn a python program to check if a year is a leap year or not with a very simple explanation but before writing a program let’s understand what is a leap year.

What is Leap Year ?

In a Leap year, there are 29 days in the month of February (which means that there are 366 days in that year) and a Leap Year arrives in the gap of every four years.

Mathematically,

• If the year is divisible by 4, it is a leap year.
• However, if the year is divisible by 100, it is not a leap year, unless… the year is also divisible by 400, in that case it is a leap year.

For Example: 2000, 2004, 2008, 2012, 2016, 2020, … etc are Leap years.

Now let us understand the implementation part with the help of a flowchart.

Flowchart for Leap Year

Now we know how to implement a python program to check if a year is a leap year or not but before writing a program few programming concepts you have to know:

1. how to take input from the user &
2. nested if-else

Source Code

year = int(input('Enter your Year: '))

if year % 4 == 0:
    if year % 100 == 0:
        if year % 400 ==0:
            print(f"{year} is a Leap year")
        else:
            print(f"{year} is Not a Leap year")
    else:
        print(f"{year} is a Leap year")
else:
    print(f"{year} is Not a Leap year")

Output-1

Enter your Year: 2000 2000 is a Leap year

Output-2

Enter your Year: 2010 2010 is Not a Leap year

Let us modify the above program and write it using a Function.

Leap Year Program in Python Using a Function

A question may be asked Like: Write a Python program to check if a year is a leap year or not using a function.

Few programming concepts you have to know before writing this program:

1. how to take input from the user
2. nested if-else &
3. Python Functions

Source Code

def check_leap_year(year):
    if year % 4 == 0:
        if year % 100 == 0:
            if year % 400 ==0:
                return f"{year} is a Leap year"
            else:
                return f"{year} is Not a Leap year"
        else:
            return f"{year} is a Leap year"
    else:
        return f"{year} is Not a Leap year"
    
my_year = int(input('Enter your Year: '))

print(check_leap_year(my_year))

Output-1

Enter your Year: 1992 1992 is a Leap year

Output-2

Enter your Year: 2002 2002 is Not a Leap year