The complement of an integer is the integer you get when you flip all the 0's to 1's and all the 1's to 0's in its binary representation.
5 is "101" in binary and its complement is "010" which is the integer 2.Given an integer num, return its complement.
Example 1:
Input: num = 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: num = 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.
Constraints:
1 <= num < 231
Note: This question is the same as 1009: https://leetcode.com/problems/complement-of-base-10-integer/