題目地址:https://leetcode.com/problems/bitwise-and-of-numbers-range/spa
題目解析:參考https://leetcode.com/problems/number-of-1-bits/,咱們知道n&n-1爲n和n-1二者左邊相同的部分,那麼容易獲得n-1&n-2爲n-2與n-1左邊相同部分,依次類推,m&m+1....&n爲m與n左邊相同部分。code
題目解答:blog
public class Solution { public int rangeBitwiseAnd(int m, int n) { int steps = 0; while(m!=n){ m>>=1; n>>=1; steps++; } return m<<steps; } }