diff --git a/232ImplementQueueusingStacks.js b/232ImplementQueueusingStacks.js
new file mode 100644
index 00000000..ec285cb7
--- /dev/null
+++ b/232ImplementQueueusingStacks.js
@@ -0,0 +1,50 @@
+var MyQueue = function () {
+  this.inStack = [];
+  this.outStack = [];
+};
+
+/**
+ * @param {number} x
+ * @return {void}
+ */
+MyQueue.prototype.push = function (x) {
+  this.inStack.push(x);
+};
+
+MyQueue.prototype.transfer = function () {
+  if (this.outStack.length === 0)
+    while (this.inStack.length != 0) {
+      this.outStack.push(this.inStack.pop());
+    }
+};
+/**
+ * @return {number}
+ */
+MyQueue.prototype.pop = function () {
+  this.transfer();
+  return this.outStack.pop();
+};
+
+/**
+ * @return {number}
+ */
+MyQueue.prototype.peek = function () {
+  this.transfer();
+  return this.outStack[this.outStack.length - 1];
+};
+
+/**
+ * @return {boolean}
+ */
+MyQueue.prototype.empty = function () {
+  return this.inStack.length === 0 && this.outStack.length === 0;
+};
+
+/**
+ * Your MyQueue object will be instantiated and called as such:
+ * var obj = new MyQueue()
+ * obj.push(x)
+ * var param_2 = obj.pop()
+ * var param_3 = obj.peek()
+ * var param_4 = obj.empty()
+ */
diff --git a/706DesignHashMap.js b/706DesignHashMap.js
new file mode 100644
index 00000000..7849b5ec
--- /dev/null
+++ b/706DesignHashMap.js
@@ -0,0 +1,79 @@
+function ListNode(key, value, next = null) {
+  this.key = key;
+  this.value = value;
+  this.next = next;
+}
+
+var MyHashMap = function () {
+  this.SIZE = 10009;
+  this.buckets = new Array(this.SIZE).fill(null);
+};
+
+MyHashMap.prototype.hash = function (key, value) {
+  return key % this.SIZE;
+};
+/**
+ * @param {number} key
+ * @param {number} value
+ * @return {void}
+ */
+MyHashMap.prototype.put = function (key, value) {
+  const idx = this.hash(key);
+  if (!this.buckets[idx]) this.buckets[idx] = new ListNode(-1, -1);
+  let prev = this.buckets[idx];
+  let curr = prev.next;
+
+  while (curr) {
+    if (curr.key == key) {
+      curr.value = value;
+      return;
+    }
+    prev = curr;
+    curr = curr.next;
+  }
+  prev.next = new ListNode(key, value);
+};
+
+/**
+ * @param {number} key
+ * @return {number}
+ */
+MyHashMap.prototype.get = function (key) {
+  const idx = this.hash(key);
+  if (!this.buckets[idx]) return -1;
+  let prev = this.buckets[idx];
+  let curr = prev.next;
+  while (curr) {
+    if (curr.key == key) return curr.value;
+    curr = curr.next;
+  }
+  return -1;
+};
+
+/**
+ * @param {number} key
+ * @return {void}
+ */
+MyHashMap.prototype.remove = function (key) {
+  const idx = this.hash(key);
+  if (!this.buckets[idx]) return;
+
+  let prev = this.buckets[idx];
+  let curr = prev.next;
+  while (curr) {
+    if (curr.key === key) {
+      prev.next = curr.next;
+      return;
+    }
+    prev = curr;
+    curr = curr.next;
+  }
+};
+
+/**
+ * Your MyHashMap object will be instantiated and called as such:
+ * var obj = new MyHashMap()
+ * obj.put(key,value)
+ * var param_2 = obj.get(key)
+ * obj.remove(key)
+ */