Add solution #1720

Author: JoshCrozier

README.md

@@ -1,4 +1,4 @@
-# 1,498 LeetCode solutions in JavaScript
+# 1,499 LeetCode solutions in JavaScript
 
 [https://leetcodejavascript.com](https://leetcodejavascript.com)
 
@@ -1325,6 +1325,7 @@
 1717|[Maximum Score From Removing Substrings](./solutions/1717-maximum-score-from-removing-substrings.js)|Medium|
 1718|[Construct the Lexicographically Largest Valid Sequence](./solutions/1718-construct-the-lexicographically-largest-valid-sequence.js)|Medium|
 1719|[Number Of Ways To Reconstruct A Tree](./solutions/1719-number-of-ways-to-reconstruct-a-tree.js)|Hard|
+1720|[Decode XORed Array](./solutions/1720-decode-xored-array.js)|Easy|
 1726|[Tuple with Same Product](./solutions/1726-tuple-with-same-product.js)|Medium|
 1732|[Find the Highest Altitude](./solutions/1732-find-the-highest-altitude.js)|Easy|
 1748|[Sum of Unique Elements](./solutions/1748-sum-of-unique-elements.js)|Easy|

solutions/1720-decode-xored-array.js

@@ -0,0 +1,30 @@
+/**
+ * 1720. Decode XORed Array
+ * https://leetcode.com/problems/decode-xored-array/
+ * Difficulty: Easy
+ *
+ * There is a hidden integer array arr that consists of n non-negative integers.
+ *
+ * It was encoded into another integer array encoded of length n - 1, such that
+ * encoded[i] = arr[i] XOR arr[i + 1]. For example, if arr = [1,0,2,1], then encoded = [1,2,3].
+ *
+ * You are given the encoded array. You are also given an integer first, that is the first
+ * element of arr, i.e. arr[0].
+ *
+ * Return the original array arr. It can be proved that the answer exists and is unique.
+ */
+
+/**
+ * @param {number[]} encoded
+ * @param {number} first
+ * @return {number[]}
+ */
+var decode = function(encoded, first) {
+  const result = [first];
+
+  for (let i = 0; i < encoded.length; i++) {
+    result.push(result[i] ^ encoded[i]);
+  }
+
+  return result;
+};