combinations with two elements
list, permutation, python
Solution
Consider using the `combinations` function in Python's `itertools` module:
>>> list(itertools.combinations('ABC', 2))
[('A', 'B'), ('A', 'C'), ('B', 'C')]
This does what it says: give me all combinations with two elements from the sequence `'ABC'`.
Problem
With python. It's possible to permute elements in a list with this method: ``` def perms(seq): if len(seq) <= 1: perms = [seq] else: perms = [] for i in range(len(seq)): sub = perms(seq[:i]+seq[i+1:]) for p in sub: perms.append(seq[i:i+1]+p) return perms ``` if a list is: seq = ['A', 'B', 'C'], the result will be.. [['A', 'B', 'C'], ['A', 'C', 'B'], ['B', 'A', 'C'], ['B', 'C', 'A'], ['C', 'A', 'B'], ['C', 'B', 'A']] HOW TO modify this method, to make permutations two terms a time? I mean, if the list is: seq = ['A', 'B', 'C']. I wanna receive [['A', 'B'], ['A', 'C'], ['B', 'C']. I can't do it. I'm trying but I can't. Thanks for the help.