Create Valid Parentheses

Public/Valid Parentheses

@@ -0,0 +1,30 @@
+// link- https://leetcode.com/problems/valid-parentheses/
+// Question:
+// Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.
+
+// An input string is valid if:
+
+// 1. Open brackets must be closed by the same type of brackets.
+// 2. Open brackets must be closed in the correct order.
+
+
+
+class Solution {
+    public boolean isValid(String s) {
+        LinkedList<Character> stack = new LinkedList<>();
+        for(int i = 0; i < s.length(); i++) {
+            char ch = s.charAt(i);
+            if(ch == '(' || ch == '[' || ch == '{') {
+                stack.addFirst(ch);
+            } else {
+                if(ch == ')' && stack.size() > 0  && stack.getFirst() == '(') stack.removeFirst();
+                else if(ch == ']' && stack.size() > 0  && stack.getFirst() == '[') stack.removeFirst();
+                else if(ch == '}' && stack.size() > 0  && stack.getFirst() == '{') stack.removeFirst();
+                else return false;
+            }
+        }
+
+        if(stack.size() > 0) return false;
+        return true;
+    }
+}