Question is pretty straight-forward.

You are given a set of 'n' numbers. You need to find total pairs of numbers whose sum is divisible by 5.

Note: Pair of numbers means collection of any two numbers from the set.

See sample test-case for more understanding.

Input format:

First line consist of total numbers given as 'n'.

Next Line consists of 'n' numbers seperated by space.

Output format:

Output total pairs whose sum is divisible by 5.

Constraints:

1 <= n <= 10^6

1 <= number <= 10^6