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Questions tagged [tarjans-algorithm]

Tarjan's algorithm is a linear-time algorithm for finding all strongly-connected components of a directed graph.

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Tarjan cycle detection help C#

Here is a working C# implementation of tarjan's cycle detection. The algorithm is found here: http://en.wikipedia.org/wiki/Tarjan%27s_strongly_connected_components_algorithm public class TarjanCycleDetect { private static…
user623879
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Functional implementation of Tarjan's Strongly Connected Components algorithm

I went ahead and implemented the textbook version of Tarjan's SCC algorithm in Scala. However, I dislike the code - it is very imperative/procedural with lots of mutating states and book-keeping indices. Is there a more "functional" version of the…
pathikrit
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How do I learn Tarjan's algorithm?

I have been trying to learn Tarjan's algorithm from Wikipedia for 3 hours now, but I just can't make head or tail of it. :( http://en.wikipedia.org/wiki/Tarjan's_strongly_connected_components_algorithm#cite_note-1 Why is it a subtree of the DFS…
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Tarjan's strongly connected components algorithm in python not working

I implemented the Tarjan's strongly connected components algorithm, according to wikipedia, in Python, but it isn't working. The algorithm is quite short and I cannot find any difference, so I cannot tell why it isn't working. I tried to check the…
jmora
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Does Tarjan's SCC algorithm give a topological sort of the SCC?

I've been studying SCC and algorithms about them, and I've seen that people almost always mention that Kosaraju's algorithm finds the SCC and also gives them ordered in a (reversed) topological sort. My question is: doesn't Tarjan's algorithm also…
Augusto
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Iterative version of a recursive algorithm is slower

I'm trying to implement an iterative version of Tarjan's strongly connected components (SCCs), reproduced here for your convenience (source: http://en.wikipedia.org/wiki/Tarjan%27s_strongly_connected_components_algorithm). Input: Graph G = (V,…
boo-urns
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Back edges in a graph

I'm having a hard time understanding Tarjan's algorithm for articulation points. I'm currently following this tutorial here: https://www.hackerearth.com/practice/algorithms/graphs/articulation-points-and-bridges/tutorial/. What I really can't see,…
Vlad Iordache
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Tarjan's strongly-connected components algorithm - why index in the back edge?

I'm studying Tarjan's algorithm for strongly-connected components and the way it works is clear to me. Anyway there's a line I don't understand: // Consider successors of v for each (v, w) in E do if (w.index is undefined) then // Successor w…
Dean
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Enumerating cycles in a graph using Tarjan's algorithm

I'm trying to determine the cycles in a directed graph using Tarjan's algorithm, presented in his research paper "Enumeration of the elementary circuits of a directed graph" from Septermber 1972. I'm using Python to code the algorithm, and an…
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What does lowlink mean in Tarjan's SCC algorithm?

I was reading the code in the following link http://www.cosc.canterbury.ac.nz/tad.takaoka/alg/graphalg/sc.txt I kept bumping into the word "low-link", and I have no idea what it means. I know this is a rather nooby question, but can someone explain…
turtlesoup
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Tarjan's algorithm in graph theory

I was learning Tarjan's algorithms differently for each to find strongly connected components, to find articulation points and to find bridges in a graph. All uses the concept of finding discovery time and low-link value using dfs and dfs…
Sumukh Bhat
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Non-recursive version of Tarjan's algorithm

I have the following (recursive) implementation of Tarjan's algorithm to find strongly connected components in a graph and it works fine: public class StronglyConnectedComponents { public static List> Search(Graph graph) { …
user2033412
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Implication Graph Assignment

An implication graph is a directed graph where each node is assigned either true or false and any edge u -> v implies that if u is true then v is true. I know a straightforward O(n^2) algorithm to find an assignment in a general implication graph…
Corei13
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Tarjan's algorithm: do lowest-links have to be similar for two or more nodes to be inside the same SCC

I'm having some trouble with a homework question involving using Tarjan's algorithm on a provided graph to find the particular SCC's for that graph. While (according to my professor) I have found the correct SCC's by using the pseudo-code algorithm…
JawKnee
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About tarjan algorithm, why can't we take low[v] instead of disc[v] when considering the backward edge?

I read an article about Tarjan's algorithm, blog. In this article, the author asks a question: In case two, can we take low[v] instead of disc[v] ?? . Answer is NO. If you can think why answer is NO, you probably understood the Low and Disc…
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