Given a list, the task is to write a python program that can split it into all possible tuple pairs combinations.
Input : test_list = [4, 7, 5, 1, 9]
Output : [[4, 7, 5, 1, 9], [4, 7, 5, (1, 9)], [4, 7, (5, 1), 9], [4, 7, (5, 9), 1], [4, (7, 5), 1, 9], [4, (7, 5), (1, 9)], [4, (7, 1), 5, 9], [4, (7, 1), (5, 9)], [4, (7, 9), 5, 1], [4, (7, 9), (5, 1)], [(4, 7), 5, 1, 9], [(4, 7), 5, (1, 9)], [(4, 7), (5, 1), 9], [(4, 7), (5, 9), 1], [(4, 5), 7, 1, 9], [(4, 5), 7, (1, 9)], [(4, 5), (7, 1), 9], [(4, 5), (7, 9), 1], [(4, 1), 7, 5, 9], [(4, 1), 7, (5, 9)], [(4, 1), (7, 5), 9], [(4, 1), (7, 9), 5], [(4, 9), 7, 5, 1], [(4, 9), 7, (5, 1)], [(4, 9), (7, 5), 1], [(4, 9), (7, 1), 5]]
Explanation : All pairs partitions are formed.
Input : test_list = [4, 7, 5, 1]
Output : [[4, 7, 5, 1], [4, 7, (5, 1)], [4, (7, 5), 1], [4, (7, 1), 5], [(4, 7), 5, 1], [(4, 7), (5, 1)], [(4, 5), 7, 1], [(4, 5), (7, 1)], [(4, 1), 7, 5], [(4, 1), (7, 5)]]
Explanation : All pairs partitions are formed.
Approach: Using slicing and recursion
In this, we perform all pair creation from 1st element, and using recursion multiple elements are converted into pairs by appropriate partitioning.
def pairings(test_list):
if len (test_list) < = 1 :
return [test_list]
# keeping 1st element and attaching every element with it
parts = [[test_list[ 0 ]] + ele for ele in pairings(test_list[ 1 :])]
for idx in range ( 1 , len (test_list)):
# pairing all possible from second element
parts.extend([[(test_list[ 0 ], test_list[idx])] +
ele for ele in pairings(test_list[ 1 : idx]
+ test_list[idx + 1 :])])
return parts
# initializing list test_list = [ 4 , 7 , 5 , 1 ]
# printing original list print ( "The original list is : " + str (test_list))
# calling util. function res = pairings(test_list)
# printing result print ( "Created partitions : " + str (res))
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Output:
The original list is : [4, 7, 5, 1]
Created partitions : [[4, 7, 5, 1], [4, 7, (5, 1)], [4, (7, 5), 1], [4, (7, 1), 5], [(4, 7), 5, 1], [(4, 7), (5, 1)], [(4, 5), 7, 1], [(4, 5), (7, 1)], [(4, 1), 7, 5], [(4, 1), (7, 5)]]
Time Complexity: O(n)
Auxiliary Space: O(n)