input: Write a python function to count the number of positive, negative, and zero elements in an array.
  assert count_positive_negative_zero([1, 0, -2, 3, 4, -6]) == (3, 2, 1)
  assert count_positive_negative_zero([0, 0, 0]) == (0, 0, 3)
  assert count_positive_negative_zero([-1, -2, -3, 4]) == (1, 3, 0)
output: def count_positive_negative_zero(arr):
      positive_count = sum(1 for x in arr if x > 0)
      negative_count = sum(1 for x in arr if x < 0)
      zero_count = sum(1 for x in arr if x == 0)
      return positive_count, negative_count, zero_count