diff --git a/longestValidParanthesis.java b/longestValidParanthesis.java
new file mode 100644
index 0000000..c2a1581
--- /dev/null
+++ b/longestValidParanthesis.java
@@ -0,0 +1,60 @@
+// Input:
+// 
+// 2
+// ((()
+// )()())
+//
+// Output:
+//
+// 2
+// 4
+
+import java.util.*;
+import java.text.*;
+import java.math.*;
+import java.util.regex.*;
+
+ class longestValidParanthesis
+{
+    public static void main (String[] args)
+    {
+        Scanner in = new Scanner(System.in);
+        int test = in.nextInt();
+        for(int t=0;t<test;++t){
+            String str = in.next();
+            Stack<Character> stack = new Stack<>();
+            Stack<Integer> index = new Stack<>();
+            int n = str.length();
+            int A[] = new int[n];
+            for(int i=0;i<n;++i){
+                char ch = str.charAt(i);
+                if(ch=='('){
+                    stack.push('(');
+                    index.push(i);
+                }
+                else{
+                    if(!stack.isEmpty() && stack.peek()=='('){
+                        stack.pop();
+                        A[i] = 1;
+                        A[index.pop()] = 1;
+                    }
+                    else{
+                        stack.push(')');
+                        index.push(i);
+                    }   
+                }
+            }
+            int max = 0;
+            int count = 0;
+            for(int i=0;i<n;++i)
+                if(A[i]==0){
+                    max = Math.max(max, count);
+                    count =0;
+                }
+                else
+                    ++count;
+            max = Math.max(max, count);
+            System.out.println(max);
+        }
+    }
+}