Canonicalized Input Description:

An integer N (1 ≤ N ≤ 10^5), representing some quantity or size.
A list of integers A of size N, where each integer is between 0 and 2^20-1.

### Example Input:

```
6
8 6 9 1 2 1
```

### Function Signature:
Write a function f(N, A) that takes in the input.
def f(N: int, A: List[int]):
    '''
    N: an integer
    A: a list of integers
    '''