Create Queue.js

Author: HansUXdev

03-DataStructures/Queue.js

@@ -0,0 +1,58 @@
+class Queue {
+    constructor() {
+      this.items = [];
+      this.front = 0;
+      this.rear = 0;
+    }
+  
+    // Add an item to the rear of the queue
+    enqueue(item) {
+      this.items[this.rear] = item;
+      this.rear++;
+    }
+  
+    // Remove and return the item at the front of the queue
+    dequeue() {
+      if (this.isEmpty()) {
+        throw new Error("Queue is empty");
+      }
+      const removedItem = this.items[this.front];
+      this.front++;
+      return removedItem;
+    }
+  
+    // Return the item at the front of the queue without removing it
+    peek() {
+      if (this.isEmpty()) {
+        throw new Error("Queue is empty");
+      }
+      return this.items[this.front];
+    }
+  
+    // Check if the queue is empty
+    isEmpty() {
+      return this.front === this.rear;
+    }
+  
+    // Return the number of items in the queue
+    size() {
+      return this.rear - this.front;
+    }
+  
+    // Empty the queue
+    clear() {
+      this.items = [];
+      this.front = 0;
+      this.rear = 0;
+    }
+  }
+  
+  // Example usage:
+  const queue = new Queue();
+  queue.enqueue(10);
+  queue.enqueue(20);
+  queue.enqueue(30);
+  console.log(queue.peek()); // 10
+  queue.dequeue();
+  console.log(queue.peek()); // 20
+