0476-Number-Complement.py

'''
Given a positive integer, output its complement number. The complement strategy is to flip the bits of its binary representation.

 

Example 1:

Input: 5
Output: 2
Explanation: The binary representation of 5 is 101 (no leading zero bits), and its complement is 010. So you need to output 2.
 

Example 2:

Input: 1
Output: 0
Explanation: The binary representation of 1 is 1 (no leading zero bits), and its complement is 0. So you need to output 0.
 

Note:

The given integer is guaranteed to fit within the range of a 32-bit signed integer.
You could assume no leading zero bit in the integer’s binary representation.
This question is the same as 1009: https://leetcode.com/problems/complement-of-base-10-integer/
'''
class Solution:
    def findComplement(self, num: int) -> int:
        return num ^ ((1 << len(bin(num)) - 2) - 1)