Create Dijkstra_algo.c

Dijkstra_algo.c

@@ -0,0 +1,65 @@
+#include <stdio.h>
+#include <limits.h>
+
+#define V 9 // Number of vertices in the graph
+
+// Utility function to find the vertex with minimum distance value,
+// from the set of vertices not yet included in shortest path tree
+int minDistance(int dist[], int sptSet[]) {
+    int min = INT_MAX, min_index;
+    for (int v = 0; v < V; v++)
+        if (!sptSet[v] && dist[v] <= min)
+            min = dist[v], min_index = v;
+    return min_index;
+}
+
+// Function to print the constructed distance array
+void printSolution(int dist[], int n) {
+    printf("Vertex \t Distance from Source\n");
+    for (int i = 0; i < V; i++)
+        printf("%d \t\t %d\n", i, dist[i]);
+}
+
+// Function that implements Dijkstra's algorithm for a graph
+// represented using adjacency matrix
+void dijkstra(int graph[V][V], int src) {
+    int dist[V];      // Output array. dist[i] holds shortest distance from src to i
+    int sptSet[V];    // sptSet[i] true if vertex i is included in shortest path tree
+
+    // Initialize all distances as infinite and sptSet[] as false
+    for (int i = 0; i < V; i++)
+        dist[i] = INT_MAX, sptSet[i] = 0;
+
+    dist[src] = 0; // Distance of source vertex from itself is always 0
+
+    // Find shortest path for all vertices
+    for (int count = 0; count < V - 1; count++) {
+        int u = minDistance(dist, sptSet); // Pick the minimum
+        sptSet[u] = 1; // Mark picked vertex as processed
+
+        for (int v = 0; v < V; v++)
+            // Update dist[v] if not in sptSet, there is an edge from u to v,
+            // and total weight of path from src to v through u is smaller
+            if (!sptSet[v] && graph[u][v] && dist[u] != INT_MAX
+                && dist[u] + graph[u][v] < dist[v])
+                dist[v] = dist[u] + graph[u][v];
+    }
+    printSolution(dist, V);
+}
+
+int main() {
+    // Example graph
+    int graph[V][V] = {
+        {0, 4, 0, 0, 0, 0, 0, 8, 0},
+        {4, 0, 8, 0, 0, 0, 0, 11, 0},
+        {0, 8, 0, 7, 0, 4, 0, 0, 2},
+        {0, 0, 7, 0, 9, 14, 0, 0, 0},
+        {0, 0, 0, 9, 0, 10, 0, 0, 0},
+        {0, 0, 4, 0, 10, 0, 2, 0, 0},
+        {0, 0, 0, 14, 0, 2, 0, 1, 6},
+        {8, 11, 0, 0, 0, 0, 1, 0, 7},
+        {0, 0, 2, 0, 0, 0, 6, 7, 0}
+    };
+    dijkstra(graph, 0); // Find shortest paths from vertex 0
+    return 0;
+}