queueusinglinkedlist.cpp

C++/queueusinglinkedlist.cpp

@@ -0,0 +1,68 @@
+#include<iostream>
+using namespace std;
+struct Node
+{
+    int data;
+    Node *next ;
+};
+class Queue
+{
+    Node *front, *rear;
+public:
+    Queue()
+    {
+        front = rear = NULL;  //   Initially
+    }
+    void Enqueue(int elem)    // for insertion from rear
+    {
+        Node *newnode;
+        newnode = new Node;
+        newnode->data = elem;
+        newnode->next = NULL;
+        if(front == NULL)
+            front = rear = newnode;
+        else
+        {
+            rear->next = newnode;
+            rear = newnode;
+        }
+    }
+    void Dequeue()            // for deletion from front
+    {
+        Node *temp;
+        if(front == NULL)
+            cout<<"Queue is Empty";
+        else
+        {
+            temp= front;
+            front = front->next;
+            delete temp;
+        }
+    }
+    void display()
+    {
+        Node *temp;
+        temp= front;
+        while(temp!=NULL) // (temp!= rear->next)
+        {
+            cout<<temp->data<<"\t";
+            temp = temp->next;
+        }
+        cout<<endl;
+    }
+};
+int main()
+{
+    Queue Q1;
+    Q1.Enqueue(10);
+    cout<<"Queue after First Enqueue :";
+    Q1.display();
+    cout<<"\n";
+    Q1.Enqueue(20);
+    cout<<"Queue after Second Enqueue :";
+    Q1.display();
+    cout<<"\n";
+    Q1.Dequeue();
+    cout<<"Queue after Dequeue :";
+    Q1.display();
+}