Reverse Bits

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?

Related problem: Reverse Integer

Credits:
Special thanks to @ts for adding this problem and creating all test cases.


public class Solution {
    // you need treat n as an unsigned value
    public int reverseBits(int n) {
        int t = 0;
        for(int i=0;i<32;i++) {
            int b = n & (1<<i);
            if(b!=0) {
                t = t | (1<<(31-i));
            }
        }
        return t;
    }
}