Added Data Structure & Algorithm in C-Programming 👨‍💻

Author: mahendramahara

Diff for: GRAPH/DF-and-BF-Search-in-Graph.c

@@ -0,0 +1,99 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+struct Node {
+    int vertex;
+    struct Node* next;
+};
+
+struct Graph {
+    struct Node* adjacencyList[100];
+    int visited[100];
+};
+
+void initializeGraph(struct Graph* graph, int numVertices) {
+    for (int i = 0; i < numVertices; ++i) {
+        graph->adjacencyList[i] = NULL;
+        graph->visited[i] = 0;
+    }
+}
+
+void addEdge(struct Graph* graph, int src, int dest) {
+    struct Node* newNode = (struct Node*)malloc(sizeof(struct Node));
+    newNode->vertex = dest;
+    newNode->next = graph->adjacencyList[src];
+    graph->adjacencyList[src] = newNode;
+
+    newNode = (struct Node*)malloc(sizeof(struct Node));
+    newNode->vertex = src;
+    newNode->next = graph->adjacencyList[dest];
+    graph->adjacencyList[dest] = newNode;
+}
+
+void dfs(struct Graph* graph, int startVertex) {
+    int stack[100];
+    int top = -1;
+    stack[++top] = startVertex;
+    graph->visited[startVertex] = 1;
+    while (top != -1) {
+        int currentVertex = stack[top--];
+        printf("%d ", currentVertex);
+        struct Node* current = graph->adjacencyList[currentVertex];
+        while (current != NULL) {
+            int neighbor = current->vertex;
+            if (!graph->visited[neighbor]) {
+                stack[++top] = neighbor;
+                graph->visited[neighbor] = 1;
+            }
+            current = current->next;
+        }
+    }
+}
+
+void bfs(struct Graph* graph, int startVertex) {
+    int queue[100];
+    int front = 0, rear = -1;
+    queue[++rear] = startVertex;
+    graph->visited[startVertex] = 1;
+    while (front <= rear) {
+        int currentVertex = queue[front++];
+        printf("%d ", currentVertex);
+        struct Node* current = graph->adjacencyList[currentVertex];
+        while (current != NULL) {
+            int neighbor = current->vertex;
+            if (!graph->visited[neighbor]) {
+                queue[++rear] = neighbor;
+                graph->visited[neighbor] = 1;
+            }
+            current = current->next;
+        }
+    }
+}
+
+int main() {
+    struct Graph graph;
+    int numVertices, numEdges;
+    printf("Enter the number of vertices: ");
+    scanf("%d", &numVertices);
+    initializeGraph(&graph, numVertices);
+    printf("Enter the number of edges: ");
+    scanf("%d", &numEdges);
+    printf("Enter the edges (format: src dest):\n");
+    for (int i = 0; i < numEdges; ++i) {
+        int src, dest;
+        scanf("%d %d", &src, &dest);
+        addEdge(&graph, src, dest);
+    }
+    printf("\n\nDepth-First Search (DFS) starting from vertex 0:\n");
+    dfs(&graph, 0);
+    
+    // Resetting visited array for BFS
+    for (int i = 0; i < numVertices; ++i) {
+        graph.visited[i] = 0;
+    }
+
+    printf("\n\nBreadth-First Search (BFS) starting from vertex 0:\n");
+    bfs(&graph, 0);
+
+    return 0;
+}