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Permutations by swapping: Difference between revisions
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Perm: (1, 0, 2, 3) Sign: -1</pre>
===Python:
After spotting the pattern of highest number being inserted into each perm of lower numbers from right to left, then left to right, I developed this
<lang python>def s_permutations(n):
def s_perm(items
for i, item in
# step
new_items += [item[:i] + [items - 1] + item[i:] \
else:▼
# step
for i in range(len(item) + 1)]
return [(tuple(item), -1 if i % 2 else 1)
for i, item in enumerate(
;Sample output:
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