Added BellmanFord Algorithm

BellmanFord.cpp

@@ -0,0 +1,129 @@
+#include <iostream>
+using namespace std;
+
+struct edge
+{
+    int u, v, w;
+};
+
+struct Graph
+{
+    int V, E;
+    struct edge *e;
+};
+
+struct Graph *create(int V, int E)
+{
+    struct Graph *g = new Graph;
+    g->V = V;
+    g->E = E;
+
+    g->e = new edge[E];
+    return g;
+};
+
+void ford(struct Graph *g, int S)
+{
+    int V = g->V;
+    int E = g->E;
+    int D[V];
+
+    for (int i = 0; i < V; i++)
+    {
+        D[i] = INT_MAX;
+    }
+
+    D[S] = 0;
+    for (int i = 1; i <= V - 1; i++)
+    {
+        for (int j = 0; j < E; j++)
+        {
+            int u = g->e[j].u;
+            int v = g->e[j].v;
+            int w = g->e[j].w;
+
+            if (D[u] != INT_MAX && D[u] + w < D[v])
+            {
+                D[v] = D[u] + w;
+            }
+        }
+    }
+
+    for (int j = 0; j < E; j++)
+    {
+        int u = g->e[j].u;
+        int v = g->e[j].v;
+        int w = g->e[j].w;
+
+        if (D[u] != INT_MAX && D[u] + w < D[v])
+        {
+            cout << "Err.. Negative Cycle";
+            return;
+        }
+    }
+
+    cout << "Source   Destination Distance From Source\n";
+    for (int i = 0; i < V; i++)
+        printf("%d\t\t%d\n", i, D[i]);
+
+    return;
+}
+int main()
+{
+#ifndef ONLINE_JUDGE
+    freopen("inp1.txt", "r", stdin);
+    freopen("out.txt", "w", stdout);
+#endif
+
+    ios_base::sync_with_stdio(0);
+    cin.tie(0);
+
+    int V = 5;
+    int E = 8;
+    int a, b, c, d;
+
+    struct Graph *gph = create(V, E);
+
+    /* for(int i=0;i<E;i++)
+    {
+        cin>>a>>b>>c;
+         
+         g->e[i].u = a;
+         g->e[i].v = b;
+         g->e[i].w = c;
+    }*/
+
+    gph->e[0].u = 0;
+    gph->e[0].v = 1;
+    gph->e[0].w = -1;
+
+    gph->e[1].u = 0;
+    gph->e[1].v = 2;
+    gph->e[1].w = 4;
+
+    gph->e[2].u = 1;
+    gph->e[2].v = 2;
+    gph->e[2].w = 3;
+
+    gph->e[3].u = 1;
+    gph->e[3].v = 3;
+    gph->e[3].w = 2;
+
+    gph->e[4].u = 1;
+    gph->e[4].v = 4;
+    gph->e[4].w = 2;
+
+    gph->e[5].u = 3;
+    gph->e[5].v = 2;
+    gph->e[5].w = 5;
+
+    gph->e[6].u = 3;
+    gph->e[6].v = 1;
+    gph->e[6].w = 1;
+
+    gph->e[7].u = 4;
+    gph->e[7].v = 3;
+    gph->e[7].w = -3;
+
+    ford(gph, 0);
+}