Refactor almost everything

Hard/longest-valid-parentheses/Solution.java

@@ -2,7 +2,7 @@ class Solution {
     public int longestValidParentheses(String str) {
         Stack<Integer> stack = new Stack<>();
         stack.push(-1);
-        
+
         int max = 0;
         for (int cur = 0; cur < str.length(); cur++) {
             if (str.charAt(cur) == '(') {

Hard/longest-valid-parentheses/solution.cpp

@@ -2,7 +2,7 @@
 #include <string>
 
 class Solution {
-  public:
+public:
     int longestValidParentheses(std::string line) {
         std::stack<int> shelf;
         shelf.push(-1);