Count the number of divisors of a positive integer n.

Examples (input --> output)

4 --> 3 (1, 2, 4).

5 --> 2 (1, 5).

12 --> 6 (1, 2, 3, 4, 6, 12).

30 --> 8 (1, 2, 3, 5, 6, 10, 15, 30).

• getDivisorsCnt(10) should return 4.
• getDivisorsCnt(11) should return 2.
• getDivisorsCnt(54) should return 8.

function getDivisorsCnt(num) {
  // code below
}