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The 3n + 1 Problem - Easy

Find the problem statement here.

The 3n + 1 problem is also known as The Collatz Conjecture in Mathematics. The problem is simple, you are given a positive integer 'n'. We perform the following operations.


  • If n = 1, Stop
  • If n is even, n = n / 2
  • If n is odd, n = 3 * n + 1
The problem statement asks to count the number of iterations we need to perform till we get to 1. (Note : 0 is a corner case.)

It's a Conjecture because it's still hasn't been proved that every number will end up at 1. 

I've decided to approach UVaOJ with C++ so that I can brush up my C++ skills. Here's my solution.

I've used recursion combined with memoization. Memoization is a type of dynamic programming. It's kind of a cache memory which stores solutions to already solved subproblems so that you don't need to solve them again.

Comments are welcome! Cheers.

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