48 lines
962 B
JavaScript
48 lines
962 B
JavaScript
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var _ = require("../lodash");
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module.exports = tarjan;
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function tarjan(g) {
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var index = 0;
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var stack = [];
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var visited = {}; // node id -> { onStack, lowlink, index }
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var results = [];
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function dfs(v) {
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var entry = visited[v] = {
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onStack: true,
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lowlink: index,
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index: index++
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};
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stack.push(v);
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g.successors(v).forEach(function(w) {
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if (!_.has(visited, w)) {
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dfs(w);
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entry.lowlink = Math.min(entry.lowlink, visited[w].lowlink);
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} else if (visited[w].onStack) {
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entry.lowlink = Math.min(entry.lowlink, visited[w].index);
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}
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});
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if (entry.lowlink === entry.index) {
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var cmpt = [];
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var w;
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do {
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w = stack.pop();
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visited[w].onStack = false;
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cmpt.push(w);
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} while (v !== w);
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results.push(cmpt);
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}
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}
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g.nodes().forEach(function(v) {
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if (!_.has(visited, v)) {
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dfs(v);
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}
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});
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return results;
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}
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