multi-fragment algorithm
{{Short description|Travelling salesman problem heuristic}}
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The multi-fragment (MF) algorithm is a heuristic or approximation algorithm for the travelling salesman problem (TSP) (and related problems). This algorithm is also sometimes called the "greedy algorithm" for the TSP.
The algorithm builds a tour for the traveling salesman one edge at a time and thus maintains multiple tour fragments, each of which is a simple path in the complete graph of cities. At each stage, the algorithm selects the edge of minimal cost that either creates a new fragment, extends one of the existing paths or creates a cycle of length equal to the number of cities.{{cite journal |last1=Johnson |first1=David |last2=A. McGeoch |first2=Lyle |title=The Traveling Salesman Problem: A Case Study in Local Optimization |journal=Local Search in Combinatorial Optimization |date=1997 |volume=1 |citeseerx=10.1.1.92.1635 }}