leetcode397

class Solution:
    def integerReplacement(self, n: int) -> int:
        count = 0
        while n != 1:
            if (n & 1) == 0: # 偶数直接右移
                n >>= 1
            else:
                n += -1 if (n & 2) == 0 or n == 3 else 1  # 奇数01或者3减一，其他加1
            count += 1
        return count

算法类型：位运算。数学技巧类型的题目，看一看解答，扩展一下思路。

参考：https://leetcode-cn.com/problems/integer-replacement/solution/wei-yun-suan-by-ma-xing/