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ford fulkerson example
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‎README.md

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### Find the MaxFlow-MinCut using Ford-Fulkerson algorithm
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The sample code below show how to obtain the MaxFlow-MinCut of a directed weighted graph using ford-fulkerson algorithm:
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The sample code below show how to obtain the MaxFlow-MinCut of a directed weighted graph using ford-fulkerson algorithm (Link: [HTML DEMO](https://rawgit.com/chen0040/js-graph-algorithms/master/examples/example-ford-fulkerson.html)):
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```javascript
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var jsgraphs = require('js-graph-algorithms');
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g.addEdge(new jsgraphs.FlowEdge(6, 2, 6));
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g.addEdge(new jsgraphs.FlowEdge(6, 7, 10));
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g.node(2).label = 'Hello';
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g.edge(0, 1).label = 'World';
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var source = 0;
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var target = 7;
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var ff = new jsgraphs.FordFulkerson(g, source, target);

‎examples/example-ford-fulkerson.html

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<html>
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<head>
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<title>
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MaxFlow-MinCut (Ford-Fulkerson)
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</title>
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<script src="../third-party-libs/vis/vis.js" type="text/javascript"></script>
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<script src="../src/jsgraphs.js" type="text/javascript"></script>
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<link href="../third-party-libs/vis/vis.css" type="text/css" />
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</head>
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<body>
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<h2>MaxFlow-MinCut (Ford-Fulkerson)</h2>
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<div id="mynetwork"></div>
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<script type="text/javascript">
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(function(){
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var g = new jsgraphs.FlowNetwork(8);
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g.addEdge(new jsgraphs.FlowEdge(0, 1, 10));
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g.addEdge(new jsgraphs.FlowEdge(0, 2, 5));
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g.addEdge(new jsgraphs.FlowEdge(0, 3, 15));
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g.addEdge(new jsgraphs.FlowEdge(1, 4, 9));
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g.addEdge(new jsgraphs.FlowEdge(1, 5, 15));
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g.addEdge(new jsgraphs.FlowEdge(1, 2, 4));
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g.addEdge(new jsgraphs.FlowEdge(2, 5, 8));
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g.addEdge(new jsgraphs.FlowEdge(2, 3, 4));
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g.addEdge(new jsgraphs.FlowEdge(3, 6, 16));
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g.addEdge(new jsgraphs.FlowEdge(4, 5, 15));
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g.addEdge(new jsgraphs.FlowEdge(4, 7, 10));
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g.addEdge(new jsgraphs.FlowEdge(5, 7, 10));
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g.addEdge(new jsgraphs.FlowEdge(5, 6, 15));
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g.addEdge(new jsgraphs.FlowEdge(6, 2, 6));
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g.addEdge(new jsgraphs.FlowEdge(6, 7, 10));
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var source = 0;
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var target = 7;
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var ff = new jsgraphs.FordFulkerson(g, source, target);
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console.log('max-flow: ' + ff.value);
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var minCut = ff.minCut(g);
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var g_nodes = [];
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var g_edges = [];
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for(var v=0; v < g.V; ++v){
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g.node(v).label = 'Node ' + v; // assigned 'Node {v}' as label for node v
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if(v == source) g.node(v).label = 'Source ' + v;
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if(v == target) g.node(v).label = 'Target ' + v;
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g_nodes.push({
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id: v,
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label: g.node(v).label,
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group: (v == source || v == target ? 2 : 5)
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});
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}
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for(var i = 0; i < minCut.length; ++i) {
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var e = minCut[i];
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e.highlighted = true;
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console.log('min-cut: (' + e.from() + ", " + e.to() + ')');
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var v = e.from();
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var w = e.to();
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g_edges.push({
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from: v,
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to: w,
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label: '' + e.flow + '/' + e.capacity,
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arrows:'to',
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color: '#ff0000'
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});
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}
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for(var v = 0; v < g.V; ++v) {
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var adj_v = g.adj(v);
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for(var i = 0; i < adj_v.length; ++i) {
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var e = adj_v[i];
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var w = e.other(v);
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if(e.highlighted) continue;
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g_edges.push({
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from: v,
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to: w,
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label: '' + e.flow + '/' + e.capacity,
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arrows:'to'
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});
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};
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}
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console.log(g.V); // display 6, which is the number of vertices in g
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console.log(g.adj(0)); // display [5, 1, 2], which is the adjacent list to vertex 0
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var nodes = new vis.DataSet(g_nodes);
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// create an array with edges
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var edges = new vis.DataSet(g_edges);
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// create a network
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var container = document.getElementById('mynetwork');
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var data = {
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nodes: nodes,
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edges: edges
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};
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var options = {};
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var network = new vis.Network(container, data, options);
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})();
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</script>
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</body>
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</html>

‎src/jsgraphs.js

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var FlowNetwork = function(V) {
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this.V = V;
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this.adjList = [];
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this.nodeInfo = [];
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for(var v = 0; v < V; ++v) {
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this.adjList.push([]);
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this.nodeInfo.push({});
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}
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};
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FlowNetwork.prototype.node = function(v) {
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return this.nodeInfo[v];
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};
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FlowNetwork.prototype.edge = function(v, w) {
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var adj_v = this.adjList[v];
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for(var i=0; i < adj_v.length; ++i) {
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var x = adj_v[i].other(v);
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if(x == w) {
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return adj_v[i];
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}
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}
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return null;
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};
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FlowNetwork.prototype.addEdge = function(e) {

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