32 lines
1.1 KiB
Markdown
32 lines
1.1 KiB
Markdown
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# cpair
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A program that searches for the closest pair of points in a set of 2D-points
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SYNOPSIS
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cpair
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EXAMPLE
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$ cat 1.txt
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4.0 4.0
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-1.0 1.0
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1.0 -1.0
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-4.0 -4.0
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$ ./cpair < 1.txt
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-1.000000 1.000000
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1.000000 -1.000000
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The program accepts an array of 2D-points as an input from `stdin`. The input ends at `EOF`.
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The program does the following:
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* No output if the array has one point
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* The points if the array has 2 points
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* Otherwise, the array is split in 2 parts based on the mean of X and sent to 2 different paralell child processes. The parent watches for the return code of the children and terminates with an error if any of the children exit with anything other than success.
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Algorithm description when there are more than 2 points:
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* P1 and P2 are the closest pairs for the first and the second part respectively.
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* Go through all of the pairs between the points from the first half with the second half and save the shortest one in P3.
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* Compare P1, P2 and P3 and return the shortest one to `stdout`.
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**Note: The description and the example are from the task I got from TU.**
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