permutations of lists python [duplicate]

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How to generate all permutations of a list in Python

I want to find all the permutations of a the elements in a list. but then with some conditions imposed.. umm.. Probably an example will help me explain better.

I have four lists

["1"],["0"],["a","b","c],["d","e","f"]

Now I want to have the permutations in following way:

 "10ad" ,"10bd","10cd","10ae", "10be"
 ,"10bf"..

and so on..

So basically every element (with every element)?? Now I know the very naive way to do this. But what is the pythonic way to do this? if there is any?? Any suggestions

Thanks

• Scott Hunter: If the order matters, please explain the ordering you want better; I would have expected "10ce" to come after "10be".
• frazman: @ScottHunter: the order doesnt matter actually :)

Answer 1

I think you want to use the itertools module, which is part of the standard Python distribution.

For example:

import itertools
a = ["1"]
b = ["0"]
c = ["a","b","c"]
d = ["d","e","f"]
for item in itertools.product(a, b, c, d): 
 print(item)

Edit: To be clear, the itertools.product function provides all combinations for all items in the inputted lists, not permutations. But based on OP's wording, I think this is what he/she actually wants.

• Collin Green: Great answer. This returns tuples, so slight adjustment to exactly match the question would be something like: for item in itertools.product(a,b,c,d): print '%s%s%s'%item
• Casey Kuball: Or alternatively, if you want a list of strings, you can just ''.join(item)