[Leetcode]201.bitwise and of Numbers Range

Topic

Given a range [M, n] where 0 <= m <= n <= 2147483647, return the bitwise AND of all numbers in this range, Inclus Ive.

For example, given the range [5, 7], and you should return 4.

Ideas

[5, 7] A total of three numbers (5,6,7), the binary is:

1 1 1 11

The result is 100 after the phase

[9, 11] A total of three numbers (9,10,11), the binary is:

1 001 1 010 1 011

The result is 1000 after the phase

[26, 30] a total of five numbers (26,27,28,29,30), the binary is:

one 010 one 011 each 101 110

The result is 11000 after the phase

Looking closely we can conclude that the result we are asking for is the part of the left public 1 of all the numbers in the given range, and the other bits are 0.

Code

/ *---------------------------------------* Date: 2015-04-26* sjf0115* title: 201.Bitwise and of Numbers range* website: HT   tps://leetcode.com/problems/bitwise-and-of-numbers-range/* Result: ac* Source: leetcode* Blog:-----------------------------------------* *#include <iostream>#include <vector>#include <algorithm>using namespace STD;classSolution { Public:intRangebitwiseand (intMintN) {if(M = =0){return 0; }//if        intCount =0; while(M! = N) {//Move left oneM >>=1; N >>=1;        ++count; }//while        returnM << count; }};intMain () {solution solution;intm =9;intn = One;intresult = Solution.rangebitwiseand (m,n);//Output    cout<<result<<endl;return 0;}

Run time

[Leetcode]201.bitwise and of Numbers Range