IV Olimpiada Informatyczna 1996/1997
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Task: TRO
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Author: Wojciech Guzicki
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III stage contest |
Source file | TRO.??? (e.g. PAS,C, CPP) |
Executable file | TRO.EXE |
Input file | TRO.IN |
Output file | TRO.OUT |
There are n points given in a space. There are no three points, such that they lie on the same straight line. Each pair of points is connected by a segment coloured red or black. Each triangle, whose sides have the same colour is called a monochromatic triangle. We are given a list of all red segments and we want to find the number of all monochromatic triangles.
In the second line of the same file there is one integer m, 0 <= m <= 250000, which equals the number of red segments.
In each of the following m lines there are two integers p and k separated by a single space, 1 <= p < k <= n. They are numbers of vertices which are ends of a red segment.
6 9 1 2 2 3 2 5 1 4 1 6 3 4 4 5 5 6 3 6the correct solution is the text file TRO.OUT
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