Total Matches in a Tournament

In a tournament where every player competes against every other player exactly once, the total number of matches is determined by the formula:

\( \frac{n(n-1)}{2} \)

Your task is to calculate the total number of matches played given the number of players n.

inputFormat

The input consists of a single integer n (number of players).

outputFormat

Output a single integer representing the total number of matches played in the tournament.

## sample

4

6

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