An integer H (2 ≤ H ≤ 10^9), representing some quantity or size.
An integer W (2 ≤ W ≤ 10^9), representing some quantity or size.
An integer S (1 ≤ S ≤ H), representing some position.
An integer T (1 ≤ T ≤ W), representing some position.

### Example Input:

```
4 5 2 3
```

### Function Signature:
Write a function f(H, W, S, T) that takes in the input. 
def f(H: int, W: int, S: int, T: int): 
    ''' 
    H: an integer 
    W: an integer 
    S: an integer 
    T: an integer 
    '''