Over a million developers have joined DZone.
{{announcement.body}}
{{announcement.title}}

Thursday Code Puzzler: The All Knowing Calendar

DZone's Guide to

Thursday Code Puzzler: The All Knowing Calendar

· Java Zone ·
Free Resource

Get the Edge with a Professional Java IDE. 30-day free trial.

By now you should be familiar with our Thursday Code Puzzler slot. The idea is simple: solve the coding problem as efficiently as you can, in any language or framework that you think is suitable.

Note: Even though there really is nothing stopping you from finding a solution to this on the internet, try to keep honest, and come up with your own answer.  It's all about the participation!

How Many Sundays Fell on the 1st?

Given the following information, calculate how many Sundays fell on the first of the month during the twentieth century: 

  • 1 January 1900 was a Monday 
  • A leap year occurs any year that is divisible by 4, but not on a century unless divisible by 400
  • "Thirty days has September,
    April, June and November.
    All the rest have thirty-one,
    Saving February alone,
    Which has twenty-eight, rain or shine.
    And on leap years, twenty-nine."

 Try and make your answer as efficient as possible!

Get the Java IDE that understands code & makes developing enjoyable. Level up your code with IntelliJ IDEA. Download the free trial.

Topics:

Opinions expressed by DZone contributors are their own.

{{ parent.title || parent.header.title}}

{{ parent.tldr }}

{{ parent.urlSource.name }}