TRAVELLING SALESPERSON PROBLEMA JAVA MPJ-EXPRESS APPROACH

BY JAKOB HAUG OFTEBRO, ULRIK SAGEN AND EIRIK AASVED HOLST

THE PROBLEM

• What is the shortest closed circuit that visits all locations?

• O(n!)• NP-Hard

GENETIC ALGORITHM

PSEUDOCODE FOR SEQUENTIAL GA:Generate initial populationwhile(not finished){

evaluate fitnessevolve population

}

IN PARALLEL

PSEUDOCODE FOR PARALLEL GA:while(outerloop){ //on root processor

mixPopulation()for(innerloop){ //on each processor

evaluate fitnessevolve subPopulation

}}

PARALLELISM

• Population = n• subPopulation = n/#processors

0 1 2 3 4 5 6 7 8 90

20

40

60

80

100

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160

Seco

nds

Number of processors

GRAPHICAL EVOLUTION REPRESENTATION