338. Counting Bits

Counting Bits

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:
    def countBits(self, num: int) -> List[int]:
        d = [0 for i in range(num+1)]
        for i in range(1, num+1):
            d[i] = d[i & i-1] + 1
        return d