diff --git a/problems/js/array-wrapper.js b/problems/js/array-wrapper.js
new file mode 100644
index 0000000..ccaefe4
--- /dev/null
+++ b/problems/js/array-wrapper.js
@@ -0,0 +1,30 @@
+/**
+ * @param {number[]} nums
+ */
+var ArrayWrapper = function(nums) {
+    this.nums = nums;
+
+    return this;
+};
+
+ArrayWrapper.prototype.valueOf = function() {
+    let sum = 0;
+
+    for (let x of this.nums) {
+        sum += x;
+    }
+
+    return sum;
+}
+
+ArrayWrapper.prototype.toString = function() {
+    return `[${this.nums.join(',')}]`;
+}
+
+/**
+ * const obj1 = new ArrayWrapper([1,2]);
+ * const obj2 = new ArrayWrapper([3,4]);
+ * obj1 + obj2; // 10
+ * String(obj1); // "[1,2]"
+ * String(obj2); // "[3,4]"
+ */