Update 136-single-number.js

Author: everthis

136-single-number.js

@@ -7,3 +7,14 @@ const singleNumber = function(nums) {
   for(let i = 1; i< nums.length; i++) xor ^= nums[i]
   return xor
 };
+
+
+// another
+
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+const singleNumber = function(nums) {
+  return nums.reduce((ac, e) => ac ^ e, 0)
+};