Python: Generate all permutations of a list in Python

Python List: Exercise - 18 with Solution

Write a Python program to generate all permutations of a list in Python.

In mathematics, the notion of permutation relates to the act of arranging all the members of a set into some sequence or order, or if the set is already ordered, rearranging (reordering) its elements, a process called permuting. These differ from combinations, which are selections of some members of a set where order is disregarded.

In the following image each of the six rows is a different permutation of three distinct balls.

Pictorial Presentation

Sample Solution:

Python Code:

import itertools
print(list(itertools.permutations([1,2,3])))

Sample Output:

[(1, 2, 3), (1, 3, 2), (2, 1, 3), (2, 3, 1), (3, 1, 2), (3, 2, 1)] 

Explanation:

In the above exercise -

import itertools  -> Import the itertools module.

list(itertools.permutations([1,2,3])): Generate all permutations of the list [1,2,3] using the permutations() function from the itertools module. The permutations() function returns an iterator, so we need to convert it to a list to print it.

Flowchart:

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Python Code Editor:

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