D. Number of Parallelogramstime limit per test4 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard outputYou are given n points on a plane. All the points are distinct and no three of them lie on the same line. Find the number of parallelograms with the vertices at the given points.InputThe first line of the input contains integer n (1 ≤ n ≤ 2000) — the number of points.Each of the next n lines contains two integers (xi, yi) (0 ≤ xi, yi ≤ 109) — the coordinates of the i-th point.OutputPrint the only integer c — the number of parallelograms with the vertices at the given points.ExampleInput40 11 01 12 0Output1
Input40 11 01 12 0
Output1
['geometry', '*1900']