A graph can refer to a graphic (such as a chart or diagram) showing or displaying the relationship between two or more variables used, for instance, in visualizing scientific data.

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11
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1answer
902 views

Topological sort in Java

I am learning algorithms in graphs. I have implemented topological sort using Java. Kindly review my code and provide me with feedback. ...
11
votes
1answer
324 views

Variadic function with restricted types

I am designing a class which (among other things) acts as a vertex in an undirected graph. ...
10
votes
3answers
1k views

Find all paths from source to destination

Given a directed connected graphs, find all paths from source to destination. Looking for code review, optimizations and best practices. Also need help figuring out complexity, which in my best ...
9
votes
1answer
76 views

Generic Graph Library

I've been working on a generic graph library for a while now, in a bit of an off and on fashion. I realise that boost::graph exists, but it is a complex library ...
7
votes
3answers
362 views

Depth First Traversal of a Graph

I am learning how to implement a basic undirected graph and perform a depth first traversal. Please critique my code for correctness, best practices, security, and any other comments that may be ...
7
votes
1answer
1k views

Distribute random number of nodes in a range [closed]

The purpose of the following code is to get a random number of 100 nodes and to distribute these nodes randomly in range 500*500...(X,Y). This was the first step: ...
7
votes
2answers
201 views

Missing level of technical depth (Common Ancestor)

I recently have given a coding test in a reputable IT company. There were three coding questions. They refused me by saying that as we felt they didn't demonstrate the level of technical depth ...
7
votes
2answers
3k views

A* search algorithm

A* search algorithm. Looking for reviews on optimization, accuracy and best practices. ...
7
votes
2answers
945 views

Check if directed graph contains a cycle

I have solved the question, and in turn felt the need to get it reviewed. Any suggestions for clean up and optimization would help. Also please verify my complexity: Complexity: O (V + E). ...
7
votes
1answer
419 views

Find almost-shortest path more efficiently

I'm trying to solve a SPOJ problem, which is code SAMER08A at this link. The problem is that when I ran my code in my IDE with all the examples given in the problem, the code works perfectly. But ...
6
votes
3answers
977 views

Print pair representing objects from sequence of nonnegative integer pairs

There are some things I am not sure of from a professional standpoint about the "correct" way to write C++ code. I have been looking through source code produced by various opensource projects, as ...
6
votes
2answers
119 views

Clone of an undirected graph

Perform a graph clone. Verifying complexity to be O(E). Looking for code review, optimizations and best practices. ...
6
votes
1answer
129 views

Escaping the prison - finding the shortest way

I have given an assignment where I have to escape a labyrinth. The goal is to find the shortest way. I have done some research and there seem to be two strategies to solve the problem: the Depth-first ...
6
votes
1answer
48 views

Extracting nodes from a road network

My code takes 143.023 seconds for extracting nodes from a road network of city like Göteborg in Sweden. Please check it out if I can optimize it. ...
6
votes
2answers
520 views

Ford-Fulkerson algorithm

Solved the ford-fulkerson algorithm, which is too vast to explain it comprehensively here. Check Wikipedia for Ford-Fulkerson and Princeton lecture on Ford-Fulkerson. Looking for code review, ...
6
votes
1answer
134 views

Dijkstra-like routing algorithm

I've got the following code to find the shortest path between two nodes using almost-Dijkstra's-algorithm which was written for an exercise, and I'm looking for things to improve my general Scala ...
6
votes
1answer
244 views

Shortest Path in a Unit Cost DAG BFS in Hadoop

Just got done implementing a shortest path algo of a unit cost DAG BFS in Hadoop and wanting to get anyone's opinion on how I could have done it better. The main issue I see is that I lose the ...
5
votes
4answers
422 views

Compute random triplets of float pairs and average area of generated triangles

I am trying to get in a lot of practice for interviews so I am trying to write as much code as possible, and getting feed back from excellent programmers like "you". Can I get some general feed back ...
5
votes
2answers
5k views

Learning to code a graph

This is my first attempt at putting the conceptual knowledge I've gained about graphs into code. When searching for examples they all seem overly complicated, and searching for a tutorial or ...
5
votes
2answers
188 views

Map color problem: Optimize using a heap?

I've written some python code to solve the map coloring problem. In my code, I represent the problem using Territory and ...
5
votes
1answer
2k views

Prims algorithm implementation

Review this code regarding optimization, cleanup, and best practices. ...
5
votes
2answers
2k views

Implementation of Dijkstra's algorithm

Please pick my code apart and give me some feedback on how I could make it better or more simple. ...
5
votes
1answer
44 views

Generic Graph Library Part 2 : Algorithms

(This is a follow on to this question). Having given an implementation for some of the graph structures, here is a portion of the algorithms that are defined to work over them: graph_degree.hpp ...
5
votes
1answer
175 views

Code to construct a complete graph

I have tried to design a class for a complete graph. Needless to say, disadvantages of my current solution are very visible: dependent inputs have led to verification headaches. In this code we ...
5
votes
2answers
142 views

How to improve this algorithm for building a graphs closures

We have a large directed acyclic graph and a requirement to filter it by allowing a user to select certain nodes and then we remove all nodes that are not selected nodes, ancestors of those nodes, or ...
5
votes
1answer
65 views

Strongly connected components algorithm

In my Python application, I am using Tarjan's algorithm to compute strongly connected components. Unfortunately, it shows up under profiling as one of the top functions in my application (at least ...
5
votes
0answers
68 views

Finding all paths from a given graph

I need to find all paths from a given graph. I can do that for now, however my recursive code is not efficient and my graphs are very complicated, hence I need a better algorithm. ...
4
votes
1answer
670 views

Do I need to delete a vector?

I want to make a graph from input from a text file in the format: vertex1 vertex2 cost time where vertex1 and vertex2 are strings that form an edge and cost and ...
4
votes
1answer
48 views

JFreeChart Dynamic Scatter Chart

I have a model that consists of a 100 'agents' that change their x and y coordinates randomly. I use JFreeChart scatter chart to represent agents' locations. ...
4
votes
1answer
52 views

Maximize the number of nodes that could be reachable in a graph

Description of my code: I am trying to maximize the number of nodes that could be reachable in a graph. Please do not consider my main algorithm, I want it to be like that. The only parts that I need ...
4
votes
1answer
559 views

BFS and DFS in Scala

I would love it if someone could give me some suggestions for these 2 graph search functions. I am new to scala and would love to get some insight into making these more idiomatic. ...
4
votes
1answer
110 views

Modified BFS code optimizations

I need some help reviewing this code in terms of making as fast as possible. This is a modified version of BFS that does quite a bit of processing on the side. Use case: I have a large graph ...
4
votes
1answer
314 views

Dijkstra's and Prim's algorithms: correctness/efficiency

This is in preparation for a competition that only allows C++03. ...
4
votes
1answer
906 views

Javascript graph skeleton implementation

I started implementing a graph drawing application in javascript and < canvas > element, and i just wanted to hear your thought on the progress so far. I'm very open to suggestions and i'm very ...
4
votes
1answer
1k views

Coding adjacency list representing graph

I want to write some basic code on graph like DFS, BFS but before that I am coding graph representation in adjacency list, and some basic functions like ...
4
votes
1answer
127 views

Finding and returning a loopy path in a directed graph

I wrote a function in Scala to find out and return a loopy path in a directed graph. One of the arguments is a graph presented in an adjacent list, and the other is a start node. It returns a pair ...
3
votes
2answers
1k views

STL-like graph implementation

I have implemented an STL-like graph class. Could someone review it and tell me things that I could add to it? File graph.hpp ...
3
votes
1answer
595 views

My first python graph traversal review

I'm trying to solve a graph traversal problem I found, and was wondering how I could improve my implementation. Currently it seems a little convoluted and long. The problem is as follows: I have a ...
3
votes
1answer
148 views

Complete graph traversal algorithm in Prolog

Given a table, I want to explore all possible transition between the elements in the table. ex: for a table with size 3 [0,1,2], the output of the algorithm should be 0->1, 1->0, 0->2, 2->1, 1->2, ...
3
votes
1answer
295 views

DFS/BFS implementation Cormen's pseudo code

I like this site and thought if putting this dfs/bfs C++ code for Cormen pseudo code.....please give your comments ...
3
votes
1answer
133 views

Tarjan's algorithm for Strongly Connected Components without keeping SCC in stack

I've been looking for an implementation of Tarjan's algorithm in C#/C++ for a strongly-connected components in graphs, and couldn't find any implementation without use of additional Stack - most of ...
3
votes
1answer
258 views

Please review my Digraph Code in Java

can people please review my digraph code? This is used to create a directed graph of type T. The directed graph has edges and vertices with values but is directional such that nodes can loop unto ...
3
votes
1answer
100 views

Review/rate my new graph class

I have written a PHP class called "graph". It is a class that performs RESTful-like commands to a MySQL database. I have posted the GitHub repo. Here is the code as well: config.php ...
3
votes
1answer
341 views

Evaluating longest path

Here is a program which keeps track of the longest path in a graph. I think it can be written much better. ...
3
votes
2answers
82 views

Simplify an if else construct with assignment before if and else

I want to simplify an if: .. else: .. construct: ...
3
votes
1answer
64 views

Clone an undirected graph

I'm looking for code-review, optimization and best practices. Also verifying complexity to be O(E) time and O(V+E) space complexity. ...
3
votes
0answers
40 views

Thinking in 'Haskell' - when to use (state) Monads

I really enjoy Haskell but feel I still have a total beginner's style, and would like to move beyond that. The code below - for Dijkstra's shortest path algorithm - is a case in point. I feel as ...
2
votes
4answers
1k views

Depth First Search & Breadth First Search implementation

I've implemented DFS and BFS implementations. I want to check if the code is readable, contains any issues, and can be improved. GraphImplementation ...
2
votes
2answers
5k views

STL graph implementation

I'm looking for a code review on the following C++/STL graph implementation: ...