An integer A (-100 ≤ A ≤ 100), an integer B (-100 ≤ B ≤ 100), and an integer C (-100 ≤ C ≤ 100).

### Example Input:

```
15 7 5
```

### Function Signature:
Write a function f(A, B, C) that takes in the input. 
def f(A: int, B: int, C: int): 
    ''' 
    A: an integer 
    B: an integer
    C: an integer
    '''