An integer \(N\) (1 ≤ \(N\) ≤ 10000), representing some quantity or size.
An integer \(K\) (1 ≤ \(K\) ≤ 10000), representing some quantity or threshold.
An integer \(X\) (1 ≤ \(X\) ≤ 10000), greater than an integer \(Y\) (1 ≤ \(Y\) < \(X\)).

### Example Input:

```
15
3
10000
9000
```

### Function Signature:
Write a function f(N, K, X, Y) that takes in the input.
```python
def f(N: int, K: int, X: int, Y: int):
    ''' 
    N: an integer 
    K: an integer 
    X: an integer 
    Y: an integer 
    '''
```