1. Description

Reverse bits of a given 32 bits unsigned integer.

For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), return 964176192 (represented in binary as 00111001011110000010100101000000).

Follow up:
If this function is called many times, how would you optimize it?

2. Runtime Distribution

3. Submission Details

4. Example

Input: 43261596
Ouput: 964176192

5. Code

[restabs alignment="osc-tabs-right" responsive="true" icon="true" text="More" seltabcolor="#fdfdfd" seltabheadcolor="#000" tabheadcolor="blue"]
[restab title="Java" active="active"]

public int reverseBits(int n) {
	for (int i = 0; i < 16; i++) {
		int lowBit = (n >> i) & 1;
		int highBit = (n >> (31 - i)) & 1;
		if ((lowBit ^ highBit) == 1) {
			n ^= (1 << i) | (1 << 31 - i);
		}
	}
	return n;
}

[/restab]
[/restabs]

6.Test

[restabs alignment="osc-tabs-right" responsive="true" icon="true" text="More" seltabcolor="#fdfdfd" seltabheadcolor="#000" tabheadcolor="blue"]
[restab title="Java" active="active" ]

public class LeetCode0190 {
	public int reverseBits(int n) {
		for (int i = 0; i < 16; i++) {
			int lowBit = (n >> i) & 1;
			int highBit = (n >> (31 - i)) & 1;
			if ((lowBit ^ highBit) == 1) {
				n ^= (1 << i) | (1 << 31 - i);
			}
		}
		return n;
	}

	public static void main(String[] args) {
		LeetCode0190 leetcode = new LeetCode0190();
		System.out.println(leetcode.reverseBits(43261596));
	}
}

[/restab]
[/restabs]