Add solution #459

Author: JoshCrozier

README.md

@@ -14,6 +14,7 @@
 264|[Ugly Number II](./0264-ugly-number-ii.js)|Medium|
 387|[First Unique Character in a String](./0387-first-unique-character-in-a-string.js)|Easy|
 451|[Sort Characters By Frequency](./0451-sort-characters-by-frequency.js)|Medium|
+459|[Repeated Substring Pattern](./0459-repeated-substring-pattern.js)|Easy|
 606|[Construct String from Binary Tree](./0606-construct-string-from-binary-tree.js)|Easy|
 617|[Merge Two Binary Trees](./0617-merge-two-binary-trees.js)|Easy|
 648|[Replace Words](./0648-replace-words.js)|Medium|

solutions/0459-repeated-substring-pattern.js

@@ -0,0 +1,18 @@
+/**
+ * 459. Repeated Substring Pattern
+ * https://leetcode.com/problems/repeated-substring-pattern/
+ * Difficulty: Easy
+ *
+ * Given a non-empty string check if it can be constructed by taking a
+ * substring of it and appending multiple copies of the substring
+ * together. You may assume the given string consists of lowercase
+ * English letters only and its length will not exceed 10000.
+ */
+
+/**
+ * @param {string} s
+ * @return {boolean}
+ */
+var repeatedSubstringPattern = function(s) {
+  return (s + s).slice(1, s.length * 2 - 1).indexOf(s) !== -1;
+};