contains duplicate solution

Author: bhan

contains-duplicate/byol-han.js

@@ -0,0 +1,9 @@
+// Given an integer array nums, return true if any value appears at least twice in the array, and return false if every element is distinct.
+/**
+ * @param {number[]} nums
+ * @return {boolean}
+ */
+var containsDuplicate = function (nums) {
+  const uniqueSet = new Set(nums);
+  return uniqueSet.size !== nums.length;
+};