N-Queen by Genetic Algorithm

Solve N-Queen problem by Genetic Algorithm (GA) in JavaScript.

How to execute

1. First install node.js

2. Set your GA parameters at index.js:

//               N , Pop, SR, MR, ReGen, CR
var ga = new GA(200, 500, 10, 50, 10000, 75);

// N:       Number of Queens in the N×N Chess Board
// Pop:     Population size
// SR:      Selection probability %
// MR:      Mutation probability %
// ReGen:   Regeneration limitation
// CR:      Max Chromosomes Convergence Rate % 

3. Go to root folder and run below code in Bash or CMD and press Enter:
   

   $ node index.js
   

Note
This project independent from any libraries. So don't need to run npm install.

The GA executed and printed an answer like this:

Starting GA ...
generation 100, elite fitness is 2
GA ended due to the best chromosome found :)

Result: {"len":200,"genome":[112,192,199,167,105,183,38,148,85,107,126,78,116,72,160,142,155,162,74,41,49,10,177,137,4,128,80,140,123,59,181,24,120,169,110,13,197,98,81,62,125,96,91,163,90,84,79,75,132,196,9,19,102,67,164,63,48,69,45,193,36,70,46,134,95,130,106,44,157,150,170,119,117,184,1,154,86,17,180,113,30,43,188,143,7,28,173,20,26,194,56,32,175,76,190,153,178,159,2,191,115,187,83,97,64,58,35,89,39,100,5,168,165,131,152,23,189,0,3,182,186,37,141,195,18,172,6,29,21,136,77,8,149,12,60,47,14,73,138,27,114,93,33,179,99,82,103,65,55,176,146,156,34,122,144,118,61,71,133,57,127,147,51,88,108,22,42,16,171,68,11,166,185,129,94,124,174,109,151,101,50,135,121,111,52,54,92,145,158,104,161,139,31,53,66,87,198,25,40,15],"fitness":0}

Generation: 123
duration: 3073 ms

Result
Is an object that included len, genome, fitness properties. len is number of Queens or genome length. genome is an array to the N length. In this array every index is Chess board row no. and array value at that index is column no. For example result[10] = 15 means, row 10 and column 15 which has home of a Queen. And fitness is number of Queens which have collision at the Chess board. So zero fitness is the best result for the elite chromosome.

Generation
Is generation number which the best chromosome reached the zero fitness.