Bitwise And Of Numbers Range · Interview Problem

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Leetcode

Medium

Bit Manipulation

Math

Bitwise And Of Numbers Range

Compute the bitwise AND of every integer in an inclusive range.

Acceptance 0%

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Problem Statement

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

The result is the value obtained by AND-ing left, left + 1, left + 2, ..., right together.

The key challenge is to avoid iterating through the entire range when it is large.

Input Format

Two integers left and right.
It is guaranteed that 0 <= left <= right.

Output Format

Return a single integer: the bitwise AND of all integers in [left, right].

Constraints

0 <= left <= right
The range may be large, so an efficient solution is expected.

Examples

Sample cases returned by the problem API.

Example 1

Input

left = 5, right = 7

Output

Explanation

Binary forms: 5 = 101, 6 = 110, 7 = 111. The AND is 100, which is 4.

Example 2

Input

left = 0, right = 0

Output

Explanation

The range contains only one number, so the answer is 0.

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