Add Kth lexicographic permutation #1179
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Function that computes the kth lexicographic permtation of 0,1,2,...,n-1 in O(n^2) time
cclauss
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Sep 13, 2019
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Looks good to me... I added a couple of minor observations.
| for i in range(2, n): | ||
| factorials.append(factorials[-1] * i) | ||
| assert ( | ||
| 0 <= k and k < factorials[-1] * n |
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k is only needed once.
assert 0 <= k < factorials[-1] * n, "k out of bounds"
| # Find permutation | ||
| while factorials: | ||
| factorial = factorials.pop() | ||
| number = k // factorial |
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number, k = divmod(factorial) # and delete line 34
Addressed requested changes
stokhos
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* Add Kth lexicographic permutation Function that computes the kth lexicographic permtation of 0,1,2,...,n-1 in O(n^2) time * Update kth_lexicographic_permutation.py Addressed requested changes
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Function that computes the kth lexicographic permtation of 0,1,2,...,n-1 in O(n^2) time