Create Deque Implementation.js

Author: RohitVishwakarma8840

Deque/Deque Implementation.js

@@ -0,0 +1,96 @@
+class Node {
+    constructor(value) {
+        this.data = value;
+        this.prev = null;
+        this.next = null;
+    }
+}
+
+class Dequeue {
+    constructor() {
+        this.front = null;
+        this.rear = null;
+    }
+
+    // Add to the front of the dequeue
+    pushFront(value) {
+        const newNode = new Node(value);
+        if (!this.front) {
+            this.front = this.rear = newNode;
+        } else {
+            newNode.next = this.front;
+            this.front.prev = newNode;
+            this.front = newNode;
+        }
+    }
+
+    // Add to the back of the dequeue
+    pushBack(value) {
+        const newNode = new Node(value);
+        if (!this.rear) {
+            this.front = this.rear = newNode;
+        } else {
+            newNode.prev = this.rear;
+            this.rear.next = newNode;
+            this.rear = newNode;
+        }
+    }
+
+    // Remove from the front of the dequeue
+    popFront() {
+        if (!this.front) {
+            console.log("Dequeue is empty");
+            return null;
+        }
+        const value = this.front.data;
+        this.front = this.front.next;
+        if (this.front) {
+            this.front.prev = null;
+        } else {
+            this.rear = null;
+        }
+        return value;
+    }
+
+    // Remove from the back of the dequeue
+    popBack() {
+        if (!this.rear) {
+            console.log("Dequeue is empty");
+            return null;
+        }
+        const value = this.rear.data;
+        this.rear = this.rear.prev;
+        if (this.rear) {
+            this.rear.next = null;
+        } else {
+            this.front = null;
+        }
+        return value;
+    }
+
+    // Check if the dequeue is empty
+    isEmpty() {
+        return this.front === null;
+    }
+
+    // Get the front element
+    getFront() {
+        return this.front ? this.front.data : null;
+    }
+
+    // Get the rear element
+    getRear() {
+        return this.rear ? this.rear.data : null;
+    }
+}
+
+// Example usage:
+const dequeue = new Dequeue();
+dequeue.pushFront(10);
+dequeue.pushBack(20);
+dequeue.pushFront(5);
+console.log("Front element:", dequeue.getFront()); // 5
+console.log("Rear element:", dequeue.getRear());   // 20
+console.log("Popped from front:", dequeue.popFront()); // 5
+console.log("Popped from back:", dequeue.popBack());   // 20
+console.log("Is dequeue empty?", dequeue.isEmpty());   // false