Write a function that accepts two arguments: an array/list of integers and another integer (`n`). 
Determine the number of times where two integers in the array have a difference of `n`.
For example:
```
[1, 1, 5, 6, 9, 16, 27], n=4  -->  3  # (1,5), (1,5), (5,9)
[1, 1, 3, 3], n=2             -->  4  # (1,3), (1,3), (1,3), (1,3)
```
from itertools import combinations

def int_diff(arr, n):
    return sum(1 for a, b  in combinations(arr, 2) if abs(a - b) == n)
from itertools import combinations

def int_diff(arr, n):
    return sum(1 for a, b  in combinations(arr, 2) if abs(a - b) == n)