158-190. 颠倒二进制位

颠倒给定的 32 位无符号整数的二进制位(硬性拼字符串就是我的)
class Solution:
    # @param n, an integer
    # @return an integer
    def reverseBits1(self, n):
        binary_ = lambda n: "" if n == 0 else binary_(n >> 1) + str(n & 1)
        binary_str = binary_(n).rjust(32, "0")[::-1]
        ret_num = int(binary_str, 2)
        return ret_num

    def reverseBits2(self, n: int) -> int:
        return int(f'{n:032b}'[::-1], 2)

    def reverseBits(self, n):
        ret, power = 0, 31
        while n:
            ret += (n & 1) << power
            n = n >> 1
            power -= 1
        return ret


if __name__ == '__main__':
    s1 = Solution()
    n = 43261596
    root = s1.reverseBits(n)
    print(root)