feat: solve No.459

Author: BaffinLee

Diff for: 401-500/459. Repeated Substring Pattern.md

@@ -0,0 +1,65 @@
+# 459. Repeated Substring Pattern
+
+- Difficulty: Easy.
+- Related Topics: String, String Matching.
+- Similar Questions: Find the Index of the First Occurrence in a String, Repeated String Match.
+
+## Problem
+
+Given a string `s`, check if it can be constructed by taking a substring of it and appending multiple copies of the substring together.
+
+ 
+Example 1:
+
+```
+Input: s = "abab"
+Output: true
+Explanation: It is the substring "ab" twice.
+```
+
+Example 2:
+
+```
+Input: s = "aba"
+Output: false
+```
+
+Example 3:
+
+```
+Input: s = "abcabcabcabc"
+Output: true
+Explanation: It is the substring "abc" four times or the substring "abcabc" twice.
+```
+
+ 
+**Constraints:**
+
+
+	
+- `1 <= s.length <= 104`
+	
+- `s` consists of lowercase English letters.
+
+
+
+## Solution
+
+```javascript
+/**
+ * @param {string} s
+ * @return {boolean}
+ */
+var repeatedSubstringPattern = function(s) {
+    return `${s}${s}`.slice(1, s.length * 2 - 1).includes(s);
+};
+```
+
+**Explain:**
+
+nope.
+
+**Complexity:**
+
+* Time complexity : O(n).
+* Space complexity : O(n).