【leetcode】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.

 

class Solution {
public:
    int rangeBitwiseAnd(int m, int n) {
        if(m==0) return 0;

        int p=0;
        while(m!=n)
        {
            m=m>>1;
            n=n>>1;
            p++;
        }

        return m<<p;
    }
};