Longest Valid Parentheses solution

Author: joshguha

32-longestValidParentheses.js

@@ -0,0 +1,45 @@
+/**
+ * @param {string} s
+ * @return {number}
+ */
+var longestValidParentheses = function (s) {
+    let longestValidParenthesesFromIndex = (index) => {
+        let result = 0;
+        let count = 0;
+        let stack = [];
+        restOfString = s.slice(index);
+
+        for (let i = 0; i < restOfString.length; i++) {
+            let current = restOfString[i];
+            if (current === "(") {
+                count++;
+                stack.push(current);
+            } else if (current === ")") {
+                if (stack.length === 0) {
+                    break;
+                }
+                count++;
+                stack.pop();
+                if (stack.length === 0) {
+                    result = count;
+                }
+            }
+        }
+
+        return result;
+    };
+
+    let result = 0;
+
+    for (let i = 0; i < s.length; i++) {
+        let indexResult = longestValidParenthesesFromIndex(i);
+
+        if (indexResult > result) {
+            result = indexResult;
+        }
+    }
+
+    return result;
+};
+
+console.log(longestValidParentheses(")()())"));