How to resolve the algorithm Permutations by swapping step by step in the Phix programming language

Published on 12 May 2024 09:40 PM

How to resolve the algorithm Permutations by swapping step by step in the Phix programming language

Table of Contents

Problem Statement

Generate permutations of n items in which successive permutations differ from each other by the swapping of any two items. Also generate the sign of the permutation which is +1 when the permutation is generated from an even number of swaps from the initial state, and -1 for odd. Show the permutations and signs of three items, in order of generation here. Such data are of use in generating the determinant of a square matrix and any functions created should bear this in mind. Note: The Steinhaus–Johnson–Trotter algorithm generates successive permutations where adjacent items are swapped, but from this discussion adjacency is not a requirement.

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