Counting Bits
Detailed guide and Python implementation for the 'Counting Bits' problem.
Problem Statement
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.
Write a function countBits(n: int) -> List[int].
- •0 <= n <= 10^5
Examples
n = 2
[0,1,1]
0 -> 0; 1 -> 1; 2 -> 10.
n = 5
[0,1,1,2,1,2]
0 -> 0; 1 -> 1; 2 -> 1; 3 -> 2; 4 -> 1; 5 -> 2.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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