Integer Replacement

397. Integer Replacement

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

If n is even, replace n with n/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:
8

Output:
3

Explanation:
8 -> 4 -> 2 -> 1

Example 2:

Input:
7

Output:
4

Explanation:
7 -> 8 -> 4 -> 2 -> 1
or
7 -> 6 -> 3 -> 2 -> 1
public class Solution {
    public int integerReplacement(int n) {
        if (n == Integer.MAX_VALUE) {
            return 32;
        }
        
        int count = 0;
        
        while (n > 1) {
            if (n % 2 == 0) {
                n = n / 2;
            } else {
                if ((n + 1) % 4 == 0 && n != 3) {
                    n++;
                } else {
                    n--;
                }
            }
            
            count++;
        }
        
        return count;
    }
}

Hope this helps,
Michael

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