Hello
I found a smart and very concise code to
generate all permutations of a list.
I put it here if someone is interested to
figure out how it works
def permut(li, prefix=[]):
if len(li)==1:
yield prefix + li
else:
for elt in li:
li2 = li.copy()
li2.remove(elt)
yield from S(li2, prefix+[elt])
exemple of usage
>>> list(permut(['a', 'b', 'c']))
[['a', 'b', 'c'], ['a', 'c', 'b'], ['b', 'a', 'c'], ['b', 'c', 'a'],
['c', 'a', 'b'], ['c', 'b', 'a']]
>>> list(permut([0,1,2,3]))
[[0, 1, 2, 3], [0, 1, 3, 2], [0, 2, 1, 3], [0, 2, 3, 1], [0, 3, 1, 2],
[0, 3, 2, 1], [1, 0, 2, 3], [1, 0, 3, 2], [1, 2, 0, 3], [1, 2, 3, 0],
[1, 3, 0, 2], [1, 3, 2, 0], [2, 0, 1, 3], [2, 0, 3, 1], [2, 1, 0, 3],
[2, 1, 3, 0], [2, 3, 0, 1], [2, 3, 1, 0], [3, 0, 1, 2], [3, 0, 2, 1],
[3, 1, 0, 2], [3, 1, 2, 0], [3, 2, 0, 1], [3, 2, 1, 0]]
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