[Leetcode] Bitwise AND of Numbers Range

 1 public class Solution {
 2     private int solution1(int m,int n){
 3         int bitxor = 1;
 4         //如果当前两个数字不相等，那么就将两个数的最低位当前最低位清零。
 5         while(m!=n){
 6             int tmp = m & bitxor;
 7             if(tmp != 0)
 8                 m = m ^ bitxor;
 9             tmp = n & bitxor;
10             if(tmp!=0)
11                 n = n ^ bitxor;
12             bitxor = bitxor << 1;
13         }
14         return n;
15     }
16     private int solution2(int m,int n){
17         int order = 0;
18         while(m!=n){
19             m = m >> 1;
20             n = n >> 1;
21             order++;
22         }
23         return m<<order;
24     }
25     public int rangeBitwiseAnd(int m, int n) {
26         return solution2(m,n);
27     }
28 }