input: Write a function to filter an array by a given criteria. The function should take an array and a criteria function as inputs, and return an array containing only the elements that meet the criteria. If the array is empty, the function should return an empty array.
  assert filter_array([1, 2, 5, 10, 15, 20, 25, 30], lambda x: x % 5 == 0) == [5, 10, 15, 20, 25, 30]
  assert filter_array([3, 6, 9, 12, 15], lambda x: x % 3 == 0) == [3, 6, 9, 12, 15]
  assert filter_array([1, 2, 3, 4, 5], lambda x: x % 2 == 0) == [2, 4]
  assert filter_array([], lambda x: x % 2 == 0) == []
  assert filter_array([1, 3, 5, 7, 9], lambda x: x % 2 == 0) == []
output: def filter_array(arr, criteria):
      return [x for x in arr if criteria(x)]