15616번 - Divisors 다국어

You are given a sequence of n integers a₁, a₂, ..., a_n. You should determine the number of such ordered pairs (i, j), that i, j ∈ {1, ..., n}, i ≠ j and a_i is a divisor of a_j.

The first line of input contains one integer n (1 ≤ n ≤ 2,000,000). The second line contains a sequence of n integers a₁, a₂, ..., a_n (1 ≤ a_i ≤ 2,000,000).

In the first and only line of output should contain one integer, denoting the number of pairs sought.

There are 6 pars with the specified properties: (1, 2), (1, 4), (1, 5), (4, 1), (4, 2), (4, 5).