Given a range [m, n] where 0 <= m <= n <= 2147483647, return the bitwise AND of all numbers in this range, inclusive.
For example, given the range [5, 7], you should return 4.
1 class Solution { 2 public: 3 int rangeBitwiseAnd(int m, int n) { 4 if(m==0) return 0; 5 6 int p=0; 7 while(m!=n) 8 { 9 m=m>>1; 10 n=n>>1; 11 p++; 12 } 13 14 return m<<p; 15 } 16 };
【leetcode】Bitwise AND of Numbers Range
原文：http://www.cnblogs.com/jawiezhu/p/4517507.html