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Thursday Code Puzzler: The All Knowing Calendar

· Java Zone

Discover how AppDynamics steps in to upgrade your performance game and prevent your enterprise from these top 10 Java performance problems, brought to you in partnership with AppDynamics.

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!

The Java Zone is brought to you in partnership with AppDynamics. AppDynamics helps you gain the fundamentals behind application performance, and implement best practices so you can proactively analyze and act on performance problems as they arise, and more specifically with your Java applications. Start a Free Trial.


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