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floyd warshall::::



#include <bits/stdc++.h>
using namespace std;


#define V 4


#define INF 99999


void printSolution(int dist[][V]);


void floydWarshall(int graph[][V])
{

    int dist[V][V], i, j, k;

    for (i = 0; i < V; i++)
        for (j = 0; j < V; j++)
            dist[i][j] = graph[i][j];



    for (k = 0; k < V; k++) {

        for (i = 0; i < V; i++) {

            for (j = 0; j < V; j++) {

                if (dist[i][j] > (dist[i][k] + dist[k][j])
                    && (dist[k][j] != INF
                        && dist[i][k] != INF))
                    dist[i][j] = dist[i][k] + dist[k][j];
            }
        }
    }


    printSolution(dist);
}


void printSolution(int dist[][V])
{
    cout << "The following matrix shows the shortest "
            "distances"
            " between every pair of vertices \n";
    for (int i = 0; i < V; i++) {
        for (int j = 0; j < V; j++) {
            if (dist[i][j] == INF)
                cout << "INF"
                     << "     ";
            else
                cout << dist[i][j] << "     ";
        }
        cout << endl;
    }
}


int main()
{

    int graph[V][V] = { { 0, 5, INF, 10 },
                        { INF, 0, 3, INF },
                        { INF, INF, 0, 1 },
                        { INF, INF, INF, 0 } };


    floydWarshall(graph);
    return 0;
}
 


Bellmanford ;;;;;



#include <bits/stdc++.h>
using namespace std;


struct Edge {
    int src, dest, weight;
};


struct Graph {

    int V, E;


    struct Edge* edge;
};


struct Graph* createGraph(int V, int E)
{
    struct Graph* graph = new Graph;
    graph->V = V;
    graph->E = E;
    graph->edge = new Edge[E];
    return graph;
}


void printArr(int dist[], int n)
{
    printf("Vertex   Distance from Source\n");
    for (int i = 0; i < n; ++i)
        printf("%d \t\t %d\n", i, dist[i]);
}


void BellmanFord(struct Graph* graph, int src)
{
    int V = graph->V;
    int E = graph->E;
    int dist[V];


    for (int i = 0; i < V; i++)
        dist[i] = INT_MAX;
    dist[src] = 0;


    for (int i = 1; i <= V - 1; i++) {
        for (int j = 0; j < E; j++) {
            int u = graph->edge[j].src;
            int v = graph->edge[j].dest;
            int weight = graph->edge[j].weight;
            if (dist[u] != INT_MAX
                && dist[u] + weight < dist[v])
                dist[v] = dist[u] + weight;
        }
    }


    for (int i = 0; i < E; i++) {
        int u = graph->edge[i].src;
        int v = graph->edge[i].dest;
        int weight = graph->edge[i].weight;
        if (dist[u] != INT_MAX
            && dist[u] + weight < dist[v]) {
            printf("Graph contains negative weight cycle");
            return;
        }
    }

    printArr(dist, V);

    return;
}


int main()
{

    int V = 5;
    int E = 8;
    struct Graph* graph = createGraph(V, E);


    graph->edge[0].src = 0;
    graph->edge[0].dest = 1;
    graph->edge[0].weight = -1;


    graph->edge[1].src = 0;
    graph->edge[1].dest = 2;
    graph->edge[1].weight = 4;


    graph->edge[2].src = 1;
    graph->edge[2].dest = 2;
    graph->edge[2].weight = 3;


    graph->edge[3].src = 1;
    graph->edge[3].dest = 3;
    graph->edge[3].weight = 2;


    graph->edge[4].src = 1;
    graph->edge[4].dest = 4;
    graph->edge[4].weight = 2;


    graph->edge[5].src = 3;
    graph->edge[5].dest = 2;
    graph->edge[5].weight = 5;


    graph->edge[6].src = 3;
    graph->edge[6].dest = 1;
    graph->edge[6].weight = 1;


    graph->edge[7].src = 4;
    graph->edge[7].dest = 3;
    graph->edge[7].weight = -3;


    BellmanFord(graph, 0);

    return 0;
}