190. Reverse Bits

public class Solution {
    // you need treat n as an unsigned value
    public int reverseBits(int n) {
        int res=0;
        for(int i=0;i<32;i++)
        {
            int yuan=1;
            int temp=yuan<<i;
            if(i<=15)
                res=((temp&n)<<(31-2*i)|res);
            else
                res=((temp&n)>>>((i-15)*2-1)|res);
        }
        return res;
    }
}