Leetcode 397 - Integer repalcement

Note:

• A really typical DFS + Memo problem.

Question:

Given a positive integer n, you can apply one of the following operations:

• If n is even, replace n with n / 2.
• If n is odd, replace n with either n + 1 or n - 1.

Return the minimum number of operations needed for n to become 1.

Example:

Code: