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.
Python3
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 listtest_list = [4, 7, 5, 1]# printing original listprint("The original list is : " + str(test_list))# calling util. functionres = pairings(test_list)# printing resultprint("Created partitions : " + str(res)) |
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)
