28. Counting Bits.cpp

/*

Given a non negative integer number num. For every numbers i in the range 0 ≤ i ≤ num calculate the number of 1's in their binary representation and return them as an array.

Example 1:
Input: 2
Output: [0,1,1]

Example 2:
Input: 5
Output: [0,1,1,2,1,2]

*/

class Solution {
public:
    
    int setBitCount(int num)
    {
        int count = 0;
        
        while(num)
        {
            count+=num&1;
            num>>=1;
        }
    return count;
    }
    
    
    vector<int> countBits(int num) 
    {
        vector<int>result;
        
        for(int i=0;i<=num;i++)
        {
            result.push_back(setBitCount(i));
        }
    return result;
    }
};