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Sorting: How to get permutation index?

In C: Instead of actually sorting an array, how would you go about obtaining the index array mapping the sorted array to the original? The solution I have seen (http://www.freshsources.com/199300F2.HTM#00F2_007D) declares the array to be sorted globally at the top, creates a compare function that compares elements in this array and hands it to qsort (with an index array). This works in the hypothetical case that you know the array you want to sort before you write your code, but what is the workaround when the array is found at run time?
Sep 17 '06 #1
1 3037
In the hypothetical case that anybody else would be as stupid as me: You only have to DECLARE the array to be sorted globally whereas you can fill in the values locally in your subroutines as you get to them.
Sep 21 '06 #2

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