Updated

C/algo

@@ -0,0 +1,108 @@
+//Implement Breadth First Search
+
+#include<stdio.h>
+#include<stdlib.h>
+#define MAX 100  
+#define initial 1
+#define waiting 2
+#define visited 3
+int n;    
+int adj[MAX][MAX];
+int state[MAX]; 
+void create_graph();
+void BF_Traversal();
+void BFS(int v);
+int queue[MAX], front = -1,rear = -1;
+void insert_queue(int vertex);
+int delete_queue();
+int isEmpty_queue();
+int main()
+{
+    create_graph();
+    BF_Traversal();
+    return 0;
+}
+void BF_Traversal()
+{
+    int v;  
+    for(v=0; v<n; v++) 
+        state[v] = initial;
+    printf("Enter Start Vertex for BFS: \n");
+    scanf("%d", &v);
+    BFS(v);
+}
+void BFS(int v)
+{
+    int i;  
+    insert_queue(v);
+    state[v] = waiting;
+    while(!isEmpty_queue())
+    {
+        v = delete_queue( );
+        printf("%d ",v);
+        state[v] = visited;
+        for(i=0; i<n; i++)
+        {
+            if(adj[v][i] == 1 && state[i] == initial) 
+            {
+                insert_queue(i);
+                state[i] = waiting;
+            }
+        }
+    }
+    printf("\n");
+} 
+void insert_queue(int vertex)
+{
+    if(rear == MAX-1)
+        printf("Queue Overflow\n");
+    else
+    {
+        if(front == -1) 
+            front = 0;
+        rear = rear+1;
+        queue[rear] = vertex ;
+    }
+}
+int isEmpty_queue()
+{
+    if(front == -1 || front > rear)
+        return 1;
+    else
+        return 0;
+}
+int delete_queue()
+{
+    int delete_item;
+    if(front == -1 || front > rear)
+    {
+        printf("Queue Underflow\n");
+        exit(1);
+    }  
+    delete_item = queue[front];
+    front = front+1;
+    return delete_item;
+}
+void create_graph()
+{
+    int count,max_edge,origin,destin;
+    printf("Enter number of vertices : ");
+    scanf("%d",&n);
+    max_edge = n*(n-1);
+    for(count=1; count<=max_edge; count++)
+    {
+        printf("Enter edge %d( -1 -1 to quit ) : ",count);
+        scanf("%d %d",&origin,&destin);
+        if((origin == -1) && (destin == -1))
+            break;
+        if(origin>=n || destin>=n || origin<0 || destin<0)
+        {
+            printf("Invalid edge!\n");
+            count--;
+        }
+        else
+        {
+            adj[origin][destin] = 1;
+        }
+    }
+}