Add solution #131

Author: JoshCrozier

README.md

@@ -90,6 +90,7 @@
 121|[Best Time to Buy and Sell Stock](./0121-best-time-to-buy-and-sell-stock.js)|Easy|
 125|[Valid Palindrome](./0125-valid-palindrome.js)|Easy|
 128|[Longest Consecutive Sequence](./0128-longest-consecutive-sequence.js)|Medium|
+131|[Palindrome Partitioning](./0131-palindrome-partitioning.js)|Medium|
 133|[Clone Graph](./0133-clone-graph.js)|Medium|
 134|[Gas Station](./0134-gas-station.js)|Medium|
 135|[Candy](./0135-candy.js)|Hard|

solutions/0131-palindrome-partitioning.js

@@ -0,0 +1,46 @@
+/**
+ * 131. Palindrome Partitioning
+ * https://leetcode.com/problems/palindrome-partitioning/
+ * Difficulty: Medium
+ *
+ * Given a string s, partition s such that every substring of the partition
+ * is a palindrome. Return all possible palindrome partitioning of s.
+ */
+
+/**
+ * @param {string} s
+ * @return {string[][]}
+ */
+var partition = function(s) {
+  return backtrack([], s);
+};
+
+function backtrack(order, string, result = []) {
+  if (!string.length) {
+    result.push(order);
+  }
+
+  for (let index = 1; index <= string.length; index++) {
+    const sliced = string.slice(0, index);
+    if (isPalindrome(sliced)) {
+      backtrack([...order, sliced], string.slice(index), result);
+    }
+  }
+
+  return result;
+}
+
+function isPalindrome(input) {
+  let right = input.length - 1;
+  let left = 0;
+
+  while (left < right) {
+    if (input[left] !== input[right]) {
+      return false;
+    }
+    left++;
+    right--;
+  }
+
+  return true;
+}