48. Count Bits

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Input: n = 2

Output: [0, 1, 1]

Explanation: 0 --> 0, 1 --> 1, 2 --> 10. Therefore, the count of 1s in each binary representation is [0, 1, 1].

Input: n = 5

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

Explanation: 0 --> 0, 1 --> 1, 2 --> 10, 3 --> 11, 4 --> 100, 5 --> 101. The counts are [0, 1, 1, 2, 1, 2].

Time Complexity

O(log n)

Space Complexity

O(1)