B'There are n segments drawn on a plane; the i -th segment connects two points ( x_{i, 1} , y_{i, 1} ) and ( x_{i, 2} , y_{i, 2} ). Each segment is non-degenerate, and is either horizontal or vertical -- formally, for every i in [1, n] either x_{i, 1} = x_{i, 2} or y_{i, 1} = y_{i, 2} (but only one of these conditions holds). Only segments of different types may intersect: no pair of horizontal segments shares any common points, and no pair of vertical segments shares any common points. We say that four segments having indices h_1 , h_2 , v_1 and v_2 such that h_1 < h_2 and v_1 < v_2 form a rectangle if the following conditions hold: Please calculate the number of ways to choose four segments so they form a rectangle. Note that the conditions h_1 < h_2 and v_1 < v_2 should hold. The first line contains one integer n ( 1 <= n <= 5000 ) -- the number of segments. Then n lines follow. The i -th line contains four integers x_{i, 1} , y_{i, 1} , x_{i, 2} and y_{i, 2} denoting the endpoints of the i -th segment. All coordinates of the endpoints are in the range [-5000, 5000] . It is guaranteed that each segment is non-degenerate and is either horizontal or vertical. Furthermore, if two segments share a common point, one of these segments is horizontal, and another one is vertical. Print one integer -- the number of ways to choose four segments so they form a rectangle. The following pictures represent sample cases: '...