Author: | A. Baranov | Time limit: | 1 sec | |
Input file: | Standard input | Memory limit: | 512 Mb | |
Output file: | Standard output |
Consider a set of N two-dimensional points represented by their coordinates (Xi, Yi).
It is required to determine the number of all possible rectangles that satisfy the following conditions:
Input starts with integer N,
followed by 2 × N integers, representing point coordinates: Xi, Yi.
The output should contain
the number of detected rectangles.
All input points are different.
− 106 ≤ (Xi, Yi) ≤ 106,
4 ≤ N ≤ 105
No. | Standard input | Standard output |
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2 |
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