Create BFS_DFS.c

Graph/BFS_DFS.c

@@ -0,0 +1,243 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+struct Node {
+    int data;
+    struct Node* next;
+};
+
+struct AdjList {
+    struct Node* head;
+};
+
+int q[20], top = -1, front = -1, rear = -1, vis[20], stack[20];
+struct AdjList adjList[20];
+int a[20][20]; // Adjacency matrix
+
+int delete();
+void add(int item);
+void bfs_matrix(int s, int n);
+void bfs_list(int s, int n);
+void dfs_matrix(int s, int n);
+void dfs_list(int s, int n);
+void push(int item);
+int pop();
+void printAdjList(int n);
+
+void main() {
+    int n, i, s, ch, j;
+    char c, dummy;
+    printf("Enter the no. of vertices : ");
+    scanf("%d", &n);
+
+    for (i = 1; i <= n; i++) {
+        adjList[i].head = NULL;
+        for (j = 1; j <= n; j++) {
+            printf("ENTER 1 IF %d HAS A NODE WITH %d ELSE 0 : ", i, j);
+            scanf("%d", &a[i][j]);
+            if (a[i][j] == 1) {
+                struct Node* newNode = (struct Node*)malloc(sizeof(struct Node));
+                newNode->data = j;
+                newNode->next = adjList[i].head;
+                adjList[i].head = newNode;
+            }
+        }
+    }
+
+    printf("THE ADJACENCY MATRIX IS : \n");
+    for (i = 1; i <= n; i++) {
+        for (j = 1; j <= n; j++) {
+            printf(" %d", a[i][j]);
+        }
+        printf("\n");
+    }
+
+    printf("THE ADJACENCY LIST IS : \n");
+    printAdjList(n);
+
+    do {
+        for (i = 1; i <= n; i++)
+            vis[i] = 0;
+        printf("\nMENU");
+        printf("\n1.B.F.S (Adjacency Matrix)");
+        printf("\n2.B.F.S (Adjacency List)");
+        printf("\n3.D.F.S (Adjacency Matrix)");
+        printf("\n4.D.F.S (Adjacency List)");
+        printf("\nEnter your choice: ");
+        scanf("%d", &ch);
+        printf("Enter the start vertex : ");
+        scanf("%d", &s);
+
+        switch (ch) {
+            case 1:
+                printf("\nBFS using Adjacency Matrix:\n");
+                bfs_matrix(s, n);
+                break;
+            case 2:
+                printf("\nBFS using Adjacency List:\n");
+                bfs_list(s, n);
+                break;
+            case 3:
+                printf("\nDFS using Adjacency Matrix:\n");
+                dfs_matrix(s, n);
+                break;
+            case 4:
+                printf("\nDFS using Adjacency List:\n");
+                dfs_list(s, n);
+                break;
+        }
+        printf("\nDO U WANT TO CONTINUE(Y/N) ?: ");
+        scanf(" %c", &c); // Add a space before %c to skip the newline character
+    } while (c == 'y' || c == 'Y');
+}
+
+void bfs_matrix(int s, int n) {
+    // BFS using adjacency matrix 
+    int p, i;
+    add(s);
+    vis[s] = 1;
+    p = delete();
+    if (p != 0)
+        printf(" %d", p);
+    while (p != 0) {
+        for (i = 1; i <= n; i++) {
+            if (a[p][i] != 0 && vis[i] == 0) {
+                add(i);
+                vis[i] = 1;
+            }
+        }
+        p = delete();
+        if (p != 0)
+            printf(" %d ", p);
+    }
+    for (i = 1; i <= n; i++)
+        if (vis[i] == 0)
+            bfs_matrix(i, n);
+}
+
+void bfs_list(int s, int n) {
+    // BFS using adjacency list
+    int p, i;
+    add(s);
+    vis[s] = 1;
+    p = delete();
+    if (p != 0)
+        printf(" %d", p);
+    while (p != 0) {
+        struct Node* current = adjList[p].head;
+        while (current != NULL) {
+            if (vis[current->data] == 0) {
+                add(current->data);
+                vis[current->data] = 1;
+            }
+            current = current->next;
+        }
+        p = delete();
+        if (p != 0)
+            printf(" %d ", p);
+    }
+    for (i = 1; i <= n; i++)
+        if (vis[i] == 0)
+            bfs_list(i, n);
+}
+
+void dfs_matrix(int s, int n) {
+    // DFS using adjacency matrix 
+    int i, k;
+    push(s);
+    vis[s] = 1;
+    k = pop();
+    if (k != 0)
+        printf(" %d ", k);
+    while (k != 0) {
+        for (i = 1; i <= n; i++) {
+            if (a[k][i] != 0 && vis[i] == 0) {
+                push(i);
+                vis[i] = 1;
+            }
+        }
+        k = pop();
+        if (k != 0)
+            printf(" %d ", k);
+    }
+    for (i = 1; i <= n; i++)
+        if (vis[i] == 0)
+            dfs_matrix(i, n);
+}
+
+void dfs_list(int s, int n) {
+    // DFS using adjacency list
+    int i, k;
+    push(s);
+    vis[s] = 1;
+    k = pop();
+    if (k != 0)
+        printf(" %d ", k);
+    while (k != 0) {
+        struct Node* current = adjList[k].head;
+        while (current != NULL) {
+            if (vis[current->data] == 0) {
+                push(current->data);
+                vis[current->data] = 1;
+            }
+            current = current->next;
+        }
+        k = pop();
+        if (k != 0)
+            printf(" %d ", k);
+    }
+    for (i = 1; i <= n; i++)
+        if (vis[i] == 0)
+            dfs_list(i, n);
+}
+
+void add(int item) {
+    if (rear == 19)
+        printf("QUEUE FULL");
+    else {
+        if (rear == -1) {
+            q[++rear] = item;
+            front++;
+        } else
+            q[++rear] = item;
+    }
+}
+
+int delete() {
+    int k;
+    if (front > rear || front == -1)
+        return (0);
+    else {
+        k = q[front++];
+        return (k);
+    }
+}
+
+void push(int item) {
+    if (top == 19)
+        printf("Stack overflow ");
+    else
+        stack[++top] = item;
+}
+
+int pop() {
+    int k;
+    if (top == -1)
+        return (0);
+    else {
+        k = stack[top--];
+        return (k);
+    }
+}
+
+void printAdjList(int n) {
+    for (int i = 1; i <= n; i++) {
+        printf("Vertex %d: ", i);
+        struct Node* current = adjList[i].head;
+        while (current != NULL) {
+            printf("%d -> ", current->data);
+            current = current->next;
+        }
+        printf("NULL\n");
+    }
+}