Day 4 Number Complement.cpp

PROBLEM:


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.


SOLUTION:


class Solution {
public:
    int findComplement(int num) {
        
        int ans=0,j;
        
        j=0;
        while(num>=(1LL<<j))
        {
            if(!(num & (1LL<<j)))
            {
                ans=ans|(1LL<<j);
            }
            
            j++;
            
        }
        
        return ans;
        
    }
};