Reverse Bits
Easy · Bit Manipulation
You are given a 32-bit unsigned integer. Return the integer that results from reversing the order of its bits, treating the number as a fixed-width 32-bit binary string. The most significant bit becomes the least significant bit and vice versa.
Examples
Input: n = 43261596 (binary 00000010100101000001111010011100)
Output: 964176192 (binary 00111001011110000010100101000000)
Why: Reading the 32-bit binary representation backwards gives the binary representation of 964176192.Input: n = 4294967293 (binary 11111111111111111111111111111101)
Output: 3221225471 (binary 10111111111111111111111111111111)
Why: Flipping the bit order of the 32-bit pattern moves the single 0 bit from position 1 to position 30 from the end.Input: n = 0
Output: 0
Why: All 32 bits are 0, so reversing them still gives all zeros.Constraints
n is given as an unsigned 32-bit integer, 0 <= n <= 2^32 - 1
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This statement is written for CodeSpeek. The problem is part of the NeetCode 150 list; Watch NeetCode's explanation of Reverse Bits. Reference solutions from the NeetCode repository (MIT) are used to verify our tests.