[LeetCode] Bitwise AND of Numbers Range

Bitwise AND of Numbers Range

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.

Credits:
Special thanks to @amrsaqr for adding this problem and creating all test cases.

Solution: The main trick we use here is to find the common left header of m, n. 

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public class Solution { public int rangeBitwiseAnd(int m, int n) { int i = 0; while (m != n) { m = m >> 1; n = n >> 1; i++; } return m << i; } }