190_Reverse_bits.cpp

class Solution {
public:
    uint32_t reverseBits(uint32_t n) {
         uint32_t ans = 0;
        for (int i = 0; i < 32; i++) {
            ans <<= 1;
            ans |= (n & 1);
            n >>= 1;
        }
        return ans;
    }
};