201. Bitwise AND of Numbers Range

Description

Given two integers left and right that represent the range [left, right], return the bitwise AND of all numbers in this range, inclusive.

 

Example 1:

Input: left = 5, right = 7
Output: 4

Example 2:

Input: left = 0, right = 0
Output: 0

Example 3:

Input: left = 1, right = 2147483647
Output: 0

 

Constraints:

  • 0 <= left <= right <= 231 - 1

Solutions

Solution 1

Python Code
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class Solution:
    def rangeBitwiseAnd(self, left: int, right: int) -> int:
        while left < right:
            right &= right - 1
        return right

Java Code
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class Solution {
    public int rangeBitwiseAnd(int left, int right) {
        while (left < right) {
            right &= (right - 1);
        }
        return right;
    }
}

C++ Code
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class Solution {
public:
    int rangeBitwiseAnd(int left, int right) {
        while (left < right) {
            right &= (right - 1);
        }
        return right;
    }
};

Go Code
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func rangeBitwiseAnd(left int, right int) int {
	for left < right {
		right &= (right - 1)
	}
	return right
}

JavaScript Code
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/**
 * @param {number} left
 * @param {number} right
 * @return {number}
 */
var rangeBitwiseAnd = function (left, right) {
    while (left < right) {
        right &= right - 1;
    }
    return right;
};

C# Code
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public class Solution {
    public int RangeBitwiseAnd(int left, int right) {
        while (left < right) {
            right &= (right - 1);
        }
        return right;
    }
}