Innovenergy_trunk/frontend/node_modules/graphlib/lib/alg/dfs.js

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var _ = require("../lodash");
module.exports = dfs;
/*
* A helper that preforms a pre- or post-order traversal on the input graph
* and returns the nodes in the order they were visited. If the graph is
* undirected then this algorithm will navigate using neighbors. If the graph
* is directed then this algorithm will navigate using successors.
*
* Order must be one of "pre" or "post".
*/
function dfs(g, vs, order) {
if (!_.isArray(vs)) {
vs = [vs];
}
var navigation = (g.isDirected() ? g.successors : g.neighbors).bind(g);
var acc = [];
var visited = {};
_.each(vs, function(v) {
if (!g.hasNode(v)) {
throw new Error("Graph does not have node: " + v);
}
doDfs(g, v, order === "post", visited, navigation, acc);
});
return acc;
}
function doDfs(g, v, postorder, visited, navigation, acc) {
if (!_.has(visited, v)) {
visited[v] = true;
if (!postorder) { acc.push(v); }
_.each(navigation(v), function(w) {
doDfs(g, w, postorder, visited, navigation, acc);
});
if (postorder) { acc.push(v); }
}
}