Question

I am trying to create a directed graph data structure in JavaScript. I want each node in the graph to be doubly-linked, so that I can obtain a list of links that each node points to, as well as the links that point to that node. Each node is an array with 3 elements, like so: [["node that links to node a"], "node a", ["node that node a links to"]]

//The functions linkNodes and unlinkNodes should add and remove nodes links from the directed graph, respectively.
var nodes = new Object();

function linkNodes(a, b){
    //a should be a string, and b should be a string as well
    //create the node a, if it doesn't exist yet
    //create the node b, if it doesn't exist yet
    //link the node a to the node b
}

function unlinkNodes(){
    //unlink the nodes a and b, if a and b exist
    //create the node a, if it doesn't exist yet
}

function getNode(string){
    //get the node that corresponds to the string
    //if the string doesn't exist, then return false
}

jsfiddle: http://jsfiddle.net/NTKZ9/1/​

Is there a more concise way to implement a directed graph in JavaScript, besides the one that I’ve proposed here?

Answer 1

A concise way would be to store an adjacency matrix in a two-dimensional array.