Add solution #1249

Author: JoshCrozier

README.md

@@ -40,6 +40,7 @@
 1189|[Maximum Number of Balloons](./1189-maximum-number-of-balloons.js)|Easy|
 1207|[Unique Number of Occurrences](./1207-unique-number-of-occurrences.js)|Easy|
 1232|[Check If It Is a Straight Line](./1232-check-if-it-is-a-straight-line.js)|Easy|
+1249|[Minimum Remove to Make Valid Parentheses](./1249-minimum-remove-to-make-valid-parentheses.js)|Medium|
 1252|[Cells with Odd Values in a Matrix](./1252-cells-with-odd-values-in-a-matrix.js)|Easy|
 1287|[Element Appearing More Than 25% In Sorted Array](./1287-element-appearing-more-than-25-in-sorted-array.js)|Easy|
 1290|[Convert Binary Number in a Linked List to Integer](./1290-convert-binary-number-in-a-linked-list-to-integer.js)|Easy|

solutions/1249-minimum-remove-to-make-valid-parentheses.js

@@ -0,0 +1,40 @@
+/**
+ * 1249. Minimum Remove to Make Valid Parentheses
+ * https://leetcode.com/problems/minimum-remove-to-make-valid-parentheses/
+ * Difficulty: Medium
+ *
+ * Given a string s of '(' , ')' and lowercase English characters.
+ *
+ * Your task is to remove the minimum number of parentheses ( '(' or ')',
+ * in any positions ) so that the resulting parentheses string is valid
+ * and return any valid string.
+ *
+ * Formally, a parentheses string is valid if and only if:
+ * - It is the empty string, contains only lowercase characters, or
+ * - It can be written as AB (A concatenated with B), where A and B are valid strings, or
+ * - It can be written as (A), where A is a valid string.
+ */
+
+/**
+ * @param {string} s
+ * @return {string}
+ */
+var minRemoveToMakeValid = function(s) {
+  const inputArray = s.split('');
+  const stack = [];
+
+  inputArray.forEach((letter, index) => {
+    if (letter === '(') {
+      stack.push(index);
+    } else if (letter === ')') {
+      if (stack.length) {
+        stack.pop();
+      } else {
+        inputArray[index] = '';
+      }
+    }
+  });
+
+  stack.forEach(index => inputArray[index] = '');
+  return inputArray.join('');
+};