D. Sereja and Squarestime limit per test2 secondsmemory limit per test512 megabytesinputstandard inputoutputstandard outputSereja has painted n distinct points on the plane. The coordinates of each point are integers. Now he is wondering: how many squares are there with sides parallel to the coordinate axes and with points painted in all its four vertexes? Help him, calculate this number.InputThe first line contains integer n (1 ≤ n ≤ 105). Each of the next n lines contains two integers xi, yi (0 ≤ xi, yi ≤ 105), the integers represent the coordinates of the i-th point. It is guaranteed that all the given points are distinct.OutputIn a single line print the required number of squares.ExamplesInput50 00 22 02 21 1Output1Input90 01 12 20 11 00 22 01 22 1Output5
Input50 00 22 02 21 1
Output1
['binary search', 'data structures', 'hashing', '*2300']