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Commit fb134b1

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vedas-dixitgithub-actionsappgurueu
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Implemented M Coloring Problem (TheAlgorithms#1562)
* Implemented M Coloring Problem * Implemented M Coloring Problem * Switch to a functional approach instead of class-based. Use proper JSDoc comments. Refine the comments and remove redundancies. * Updated Documentation in README.md * Proper JSDoc comment --------- Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com> Co-authored-by: Lars Müller <34514239+appgurueu@users.noreply.github.com>
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‎Backtracking/MColoringProblem.js

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/**
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* Colors a graph using up to m colors such that no two adjacent vertices share the same color.
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* @param {number[][]} graph - Adjacency matrix of the graph, using 0 for no edge.
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* @param {number} m - The number of colors to use.
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* @returns {?Array.<number>} A valid M-coloring of the graph using colors 1 to m, or null if none exists.
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* @see https://en.wikipedia.org/wiki/Graph_coloring
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*/
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function mColoring(graph, m) {
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const colors = new Array(graph.length).fill(0);
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// Check if it's safe to color a vertex with a given color.
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function isSafe(vertex, color) {
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for (let i = 0; i < graph.length; i++) {
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if (graph[vertex][i] && colors[i] === color) {
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return false;
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}
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}
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return true;
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}
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// Use backtracking to try and color the graph.
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function solveColoring(vertex = 0) {
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if (vertex === graph.length) {
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return true;
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}
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for (let color = 1; color <= m; color++) {
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if (isSafe(vertex, color)) {
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colors[vertex] = color;
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if (solveColoring(vertex + 1)) {
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return true;
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}
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// If no solution, backtrack.
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colors[vertex] = 0;
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}
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}
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return false;
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}
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// If coloring is possible, return the colors.
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if (solveColoring()) {
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return colors;
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}
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return null;
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}
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export { mColoring };
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import { mColoring } from '../MColoringProblem';
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describe('MColoringProblem', () => {
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it('should color a triangle with 3 colors', () => {
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const graph = [
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[0, 1, 1],
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[1, 0, 1],
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[1, 1, 0]
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];
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const solution = mColoring(graph, 3);
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expect(solution).not.toBeNull();
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});
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it('should not color a triangle with 2 colors', () => {
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const graph = [
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[0, 1, 1],
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[1, 0, 1],
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[1, 1, 0]
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];
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const solution = mColoring(graph, 2);
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expect(solution).toBeNull();
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});
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});

‎DIRECTORY.md

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* [generateParentheses](Backtracking/generateParentheses.js)
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* [GeneratePermutations](Backtracking/GeneratePermutations.js)
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* [KnightTour](Backtracking/KnightTour.js)
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* [MColoringProblem](Backtracking/MColoringProblem.js)
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* [NQueens](Backtracking/NQueens.js)
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* [RatInAMaze](Backtracking/RatInAMaze.js)
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* [Sudoku](Backtracking/Sudoku.js)
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* [Area](Maths/Area.js)
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* [ArithmeticGeometricMean](Maths/ArithmeticGeometricMean.js)
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* [ArmstrongNumber](Maths/ArmstrongNumber.js)
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* [AutomorphicNumber](Maths/AutomorphicNumber.js)
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* [AverageMean](Maths/AverageMean.js)
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* [AverageMedian](Maths/AverageMedian.js)
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* [BinaryConvert](Maths/BinaryConvert.js)

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