190. Reverse Bits

class Solution {
public:
    uint32_t reverseBits(uint32_t n) 
    {
        uint32_t z=2147483648;
        uint32_t x=0;
        int d;
        while(n>0)
        {
            d=n%2;
            if(d==1)
                x+=z;
            z/=2;
            n/=2;
        }
        return x;
    }
};