Design Front Middle Back Queue problem solved

Author: hasibulislam999

Data Stream/1670_design-front-middle-back-queue.js

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+/**
+ * Title: Design Front Middle Back Queue
+ * Description: Design a queue that supports push and pop operations in the front, middle, and back.
+ * Author: Hasibul Islam
+ * Date: 28/04/2023
+ */
+
+var FrontMiddleBackQueue = function () {
+  this.queue = [];
+};
+
+/**
+ * @param {number} val
+ * @return {void}
+ */
+FrontMiddleBackQueue.prototype.pushFront = function (val) {
+  this.queue.unshift(val);
+};
+
+/**
+ * @param {number} val
+ * @return {void}
+ */
+FrontMiddleBackQueue.prototype.pushMiddle = function (val) {
+  let middle = Math.floor(this.queue.length / 2);
+  this.queue.splice(middle, 0, val);
+};
+
+/**
+ * @param {number} val
+ * @return {void}
+ */
+FrontMiddleBackQueue.prototype.pushBack = function (val) {
+  this.queue.push(val);
+};
+
+/**
+ * @return {number}
+ */
+FrontMiddleBackQueue.prototype.popFront = function () {
+  if (!this.queue.length) return -1;
+  return this.queue.shift();
+};
+
+/**
+ * @return {number}
+ */
+FrontMiddleBackQueue.prototype.popMiddle = function () {
+  if (!this.queue.length) return -1;
+  let middle = Math.floor(this.queue.length / 2);
+  if (this.queue.length % 2 == 0) middle--;
+  return this.queue.splice(middle, 1);
+};
+
+/**
+ * @return {number}
+ */
+FrontMiddleBackQueue.prototype.popBack = function () {
+  if (!this.queue.length) return -1;
+  return this.queue.pop();
+};
+
+/**
+ * Your FrontMiddleBackQueue object will be instantiated and called as such:
+ * var obj = new FrontMiddleBackQueue()
+ * obj.pushFront(val)
+ * obj.pushMiddle(val)
+ * obj.pushBack(val)
+ * var param_4 = obj.popFront()
+ * var param_5 = obj.popMiddle()
+ * var param_6 = obj.popBack()
+ */