Example #1
0
        static void DestroyMinimumCut(ref NetworkGraph graph, bool isDynamic, StreamWriter write)
        {
            // get the minimum cut and sort it by highest flow.
            List <NetworkLink> minCut = FindMinimumCut(graph.source);

            int halfFlowTime     = -1;
            int totalFlowMaximum = graph.maxFlow;

            // Console.WriteLine("Beginning 'DestroyMinimumCut()'.");

            int t = 0;

            while (graph.maxFlow != 0)
            {
                minCut.Sort((x, y) => - x.flow.CompareTo(y.flow));
                graph.DestroyLink(minCut[0]);

                if (isDynamic)
                {
                    graph.FillGraph();
                }

                if (halfFlowTime == -1 && graph.maxFlow < 0.5f * totalFlowMaximum)
                {
                    halfFlowTime = t;
                }

                PrintGraphInfo(graph, t, write);
                t++;
            }
            Console.WriteLine("'DestroyMinimumCut()' complete. \t|Max flow: " + graph.maxFlow + " \t|Half flow time: " + halfFlowTime);
            write.WriteLine("MaxFlow: " + graph.maxFlow + " Half flow time: " + halfFlowTime + "\n");
        }
Example #2
0
        static void Main(string[] args)
        {
            StreamWriter outputRandom      = new StreamWriter("output_random.txt");
            StreamWriter outputHighestFlow = new StreamWriter("output_highestflow.txt");
            StreamWriter outputMincut      = new StreamWriter("output_mincut.txt");

            // number of links between source and graph, and graph and target
            for (int K = 30; K <= 60; K++)
            {
                int seed = DateTime.Now.Millisecond;
                Console.WriteLine("\t|K = " + K + " |SEED: " + seed);
                outputRandom.WriteLine("\t|K = " + K);
                outputHighestFlow.WriteLine("\t|K = " + K);
                outputMincut.WriteLine("\t|K = " + K);
                for (int j = 0; j < 2; j++)
                {
                    Console.WriteLine(j == 1 ? "\tDynamic" : "\tStatic");
                    for (int i = 0; i < 3; i++)
                    {
                        // build the graph using the file provided in the project description.
                        NetworkGraph graph = new NetworkGraph(GRAPH_FILE, VERTEX_COUNT, EDGE_COUNT, MIN_CAPACITY, MAX_CAPACITY, K, seed);

                        // fill the graph's flow to achieve the max flow.
                        graph.FillGraph();

                        // i = 0: Random Destruction
                        // i = 1: Planned Destruction
                        // j = 0: Static Routing
                        // j = 1: Dynamic routing

                        if (i == 0)
                        {
                            outputRandom.WriteLine(j == 1 ? "Dynamic" : "Static");
                            DestroyAtRandom(ref graph, j == 1, outputRandom, seed + K);
                        }
                        else if (i == 1)
                        {
                            outputHighestFlow.WriteLine(j == 1 ? "Dynamic" : "Static");
                            DestroyHighestFlowing(ref graph, j == 1, outputHighestFlow);
                        }
                        else
                        {
                            outputMincut.WriteLine(j == 1 ? "Dynamic" : "Static");
                            DestroyMinimumCut(ref graph, j == 1, outputMincut);
                        }
                    }
                }
            }

            outputRandom.Flush();
            outputHighestFlow.Flush();
            outputMincut.Flush();

            // pause so i can read the output.
            Console.ReadLine();
        }
Example #3
0
        static void DestroyHighestFlowing(ref NetworkGraph graph, bool isDynamic, StreamWriter write)
        {
            // get the list of all edges and sort it by maximum flow.
            List <NetworkLink> edges = new List <NetworkLink>();

            for (int i = 0; i < EDGE_COUNT; i++)
            {
                edges.Add(graph.edges[i]);
            }
            edges.Sort((x, y) => - x.flow.CompareTo(y.flow));

            int halfFlowTime     = -1;
            int totalFlowMaximum = graph.maxFlow;

            // Console.WriteLine("Beginning 'DestroyHighestFlowing()'");

            // destroy each edge in order.
            int t = 0;
            int j = 0;

            while (graph.maxFlow > 0)
            {
                if (!isDynamic)
                {
                    while (edges[j].flow == 0)
                    {
                        j++;
                    }
                }

                graph.DestroyLink(edges[j]);

                if (halfFlowTime == -1 && graph.maxFlow < 0.5f * totalFlowMaximum)
                {
                    halfFlowTime = t;
                }

                if (isDynamic)
                {
                    graph.FillGraph();
                    edges.Sort((x, y) => - x.flow.CompareTo(y.flow));
                }
                else
                {
                    j++;
                }

                PrintGraphInfo(graph, t, write);
                t++;
            }
            Console.WriteLine("'DestroyHighestFlowing()' complete. \t|Max flow: " + graph.maxFlow + " \t|Half flow time: " + halfFlowTime);
            write.WriteLine("MaxFlow: " + graph.maxFlow + " Half flow time: " + halfFlowTime + "\n");
        }
Example #4
0
        static void DestroyAtRandom(ref NetworkGraph graph, bool isDynamic, StreamWriter write, int seed)
        {
            // set up a list containing the indeces of the possible-to-destroy edges.
            List <int> choices = new List <int>(EDGE_COUNT);

            for (int i = 0; i < EDGE_COUNT; i++)
            {
                choices.Add(i);
            }
            int count = choices.Count;

            int halfFlowTime     = -1;
            int totalFlowMaximum = graph.maxFlow;

            // Console.WriteLine("Beginning 'DestroyAtRandom()'");

            // loop until the maximum flow has been reduced to 0.
            int t = 1;

            while (graph.maxFlow != 0)
            {
                // get a random number from 0 to the number of possible edge choices
                Random random = new Random(seed);
                int    rand   = random.Next(0, count);

                // select the int at that index as the chosen index of the edge to destroy
                int choice = choices[rand];

                // 'delete' the element that we chose (move the last element to the index that we chose, then reduce the count)
                choices[rand] = choices[count - 1];
                count--;

                // destroy the link, updating the other nodes in the graph as needed.
                graph.DestroyLink(graph.edges[choice]);

                // if the routing method is 'dynamic', then recalculate the flow path.
                if (isDynamic)
                {
                    graph.FillGraph();
                }

                if (halfFlowTime == -1 && graph.maxFlow < 0.5f * totalFlowMaximum)
                {
                    halfFlowTime = t;
                }

                PrintGraphInfo(graph, t, write);
                t++;
            }
            Console.WriteLine("'DestroyAtRandom()' complete. \t\t|Max flow: " + graph.maxFlow + " \t|Half flow time: " + halfFlowTime);
            write.WriteLine("MaxFlow: " + graph.maxFlow + " Half flow time: " + halfFlowTime + "\n");
        }
Example #5
0
 static void PrintGraphInfo(NetworkGraph graph, int t, StreamWriter write)
 {
     write.WriteLine(t + "\t" + graph.maxFlow);
 }