Given an integer n, return an array ans of length n + 1 such that for each i (0 <= i <= n), ans[i] is the number of 1's in the binary representation of i.
n
ans
n + 1
i
0 <= i <= n
ans[i]
1
0 <= n <= 10^5
n = 2
[0, 1, 1]
n = 5
[0, 1, 1, 2, 1, 2]