# Count Sundays

Learn to write a code for counting Sundays during the twentieth century.

## We'll cover the following

## Challenge

January 1st, 1900 was a Monday. The months April, June, September, and November have 30 days, whereas the rest have 31 days, except February which has 29 or 28 depending on whether the year is a leap year or not. A leap year occurs on any year evenly divisible by 4, but not on a century unless it is divisible by 400. Write a program to find out how many Sundays fell on the first of the month during the twentieth century (January 1st, 1901 to December 31st, 2000)?

Note:It is given that January 1st, 1900 was a Monday.

For this problem, you will have to write two functions:

**1.** `isLeap ( )`

This function takes a year as an integer value, returns **True** if that is a leap year, and **False** otherwise.

**2.** `numSundaysFirst( )`

This function should return the number of months in the twentieth century that started on a Sunday. It may use **isLeap ()** as a helper function.

## Coding exercise

Try to solve this challenge on your own. If you can’t solve it, you can look at the solution and explanation below.

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