WeightedGraph2.java

/*
 * Copyright (C) 2016 Naman Dwivedi
 *
 * Licensed under the GNU General Public License v3
 *
 * This is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 */

package com.naman14.algovisualizer.algorithm.graph;

//Weighted graph implementation using adjacency matrix
public class WeightedGraph2 {
    private int[][] edges;  // adjacency matrix
    private int[] labels;

    public WeightedGraph2(int n) {
        edges = new int[n][n];
        labels = new int[n];
    }


    public int size() {
        return labels.length;
    }

    public void setLabel(int vertex, int label) {
        labels[vertex] = label;
    }

    public Object getLabel(int vertex) {
        return labels[vertex];
    }

    public void addEdge(int source, int target, int w) {
        edges[source][target] = w;
    }

    public boolean isEdge(int source, int target) {
        return edges[source][target] > 0;
    }

    public void removeEdge(int source, int target) {
        edges[source][target] = 0;
    }

    public int getWeight(int source, int target) {
        return edges[source][target];
    }

    public int[] neighbors(int vertex) {
        int count = 0;
        for (int i = 0; i < edges[vertex].length; i++) {
            if (edges[vertex][i] > 0) count++;
        }
        final int[] answer = new int[count];
        count = 0;
        for (int i = 0; i < edges[vertex].length; i++) {
            if (edges[vertex][i] > 0) answer[count++] = i;
        }
        return answer;
    }
}