bitwise-and-of-numbers-range.cpp

// Given a range [m, n] where 0 <= m <= n <= 2147483647, return the bitwise AND of all numbers in this range, inclusive.
//
// Example 1:
//
//
// Input: [5,7]
// Output: 4
//
//
// Example 2:
//
//
// Input: [0,1]
// Output: 0
//


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