DFS And BFS Traversal

#include <stdio.h>
#include <stdlib.h>

// Define the maximum number of vertices in the graph
#define MAX_VERTICES 100

// Define a stack for DFS and a queue for BFS
int stack[MAX_VERTICES];
int top = -1;
int queue[MAX_VERTICES];
int front = -1, rear = -1;

int visited[MAX_VERTICES];

// Define the adjacency matrix for the graph
int graph[MAX_VERTICES][MAX_VERTICES];
int numVertices;

void push(int vertex) {
    stack[++top] = vertex;
}

int pop() {
    return stack[top--];
}

void enqueue(int vertex) {
    if (rear == MAX_VERTICES - 1)
        printf("Queue is full.\n");
    else
        queue[++rear] = vertex;
}

int dequeue() {
    if (front == rear)
        return -1; // Empty queue
    return queue[++front];
}

void initGraph(int vertices) {
    numVertices = vertices;
    for (int i = 0; i < numVertices; i++) {
        visited[i] = 0;
        for (int j = 0; j < numVertices; j++) {
            graph[i][j] = 0;
        }
    }
}

void addEdge(int start, int end) {
    graph[start][end] = 1;
}

void DFS(int vertex) {
    int u, v;
    push(vertex);

    while (top != -1) {
        u = pop();
        if (visited[u] == 0) {
            printf("Visited vertex %d\n", u);
            visited[u] = 1;
            for (v = 0; v < numVertices; v++) {
                if (graph[u][v] && !visited[v]) {
                    push(v);
                }
            }
        }
    }
}

void BFS(int vertex) {
    int u, v;
    enqueue(vertex);

    while (front != rear) {
        u = dequeue();
        if (visited[u] == 0) {
            printf("Visited vertex %d\n", u);
            visited[u] = 1;
            for (v = 0; v < numVertices; v++) {
                if (graph[u][v] && !visited[v]) {
                    enqueue(v);
                }
            }
        }
    }
}

int main() {
    int vertices, edges, startVertex;
   
    printf("Enter the number of vertices and edges: ");
    scanf("%d %d", &vertices, &edges);
    initGraph(vertices);
   
    printf("Enter the edges (format: start end):\n");
    for (int i = 0; i < edges; i++) {
        int start, end;
        scanf("%d %d", &start, &end);
        addEdge(start, end);
    }
   
    printf("Enter the starting vertex for traversal: ");
    scanf("%d", &startVertex);
   
    printf("DFS Traversal:\n");
    DFS(startVertex);
   
    // Reset visited array
    for (int i = 0; i < vertices; i++) {
        visited[i] = 0;
    }

    printf("\nBFS Traversal:\n");
    BFS(startVertex);
   
    return 0;
}