Reverse Bits

Problem

https://leetcode.com/problems/reverse-bits/

Reverse bits of a given 32 bits unsigned integer.

Example 1:

Input: n = 00000010100101000001111010011100
Output:    964176192 (00111001011110000010100101000000)
Explanation: The input binary string 00000010100101000001111010011100 represents the
unsigned integer 43261596, so return 964176192 which its binary representation is
00111001011110000010100101000000.

Example 2:

Input: n = 11111111111111111111111111111101
Output:   3221225471 (10111111111111111111111111111111)
Explanation: The input binary string 11111111111111111111111111111101 represents the
unsigned integer 4294967293, so return 3221225471 which its binary representation is
10111111111111111111111111111111.

Constraints:

The input must be a binary string of length 32.

Pattern

Bit Manipulation

Approaches

Bit Manipulation

Code

def reverseBits(n: int) -> int:
    """Reverse the bits of a 32-bit unsigned integer."""
    result = 0
    for i in range(32):
        if (1 << i) & n:
            result |= 1 << (31 - i)
    return result

Test

>>> from reverse_bits__bit_manipulation import reverseBits
>>> reverseBits(43261596)
964176192
>>> reverseBits(4294967293)
3221225471

reverse_bits__bit_manipulation.reverseBits(n: int) → int: Reverse the bits of a 32-bit unsigned integer.