Add Permutation::permute_in_place #3
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This method (as the name implies) permutes the target slice in-place with constant space rather than allocating a clone. The trade-off is worse asymptotic running time for large permutations with large cycles -- O(n^2) worst-case, but O(n log n) expected since most permutations don't have large cycles.
chrisbouchard
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I've removed the left-over |
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I think it could be handy to have a way to permute a slice without requiring
T: Cloneand without allocating aVec. This method does the permutation in-place by swapping elements. The trade-off is that it has a worse asymptotic running time — O(n²) worst-case for cyclic permutations, but (I believe) O(n log n) expected since most permutations don't have large cycles. (The slow-down comes from having to chase cycles to figure out which elements to swap.)