397. Integer Replacement

Given a positive integer n and you can do operations as follow:

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

What is the minimum number of replacements needed for n to become 1?

Example 1:

Input:8Output:3Explanation:8 -> 4 -> 2 -> 1

Example 2:

Input:7Output:4Explanation:7 -> 8 -> 4 -> 2 -> 1or7 -> 6 -> 3 -> 2 -> 1

处理一下边界，其余情况？递归大法好~

public class Solution {    public static int integerReplacement(int n){if(n==1)return 0;if(n==Integer.MAX_VALUE)return 32;if(n%2==0)return integerReplacement(n/2)+1;return Math.min(integerReplacement(n+1),integerReplacement(n-1))+1;}}