Pattern Syntax Checker

Using Regex, we can easily match or search for patterns in a text. Before searching for a pattern, we have to specify one using some well-defined syntax.

In this problem, you are given a pattern. You have to check whether the syntax of the given pattern is valid.

Note: In this problem, a regex is only valid if you can compile it using the Pattern.compile method.

Input Format

The first line of input contains an integer , denoting the number of test cases. The next  lines contain a string of any printable characters representing the pattern of a regex.

Output Format

For each test case, print Valid if the syntax of the given pattern is correct. Otherwise, print Invalid. Do not print the quotes.

Sample Input

3

([A-Z])(.+)

[AZ[a-z](a-z)

batcatpat(nat

Sample Output

Valid

Invalid

Invalid

Program:

import java.util.Scanner;

import java.util.regex.*;

public class Solution

{

    public static void main(String[] args){

        Scanner in = new Scanner(System.in);

        int testCases = Integer.parseInt(in.nextLine());

        while(testCases>0){

            String pattern = in.nextLine();

            //Write your code

            testCases--;

            try{

                Pattern.compile(pattern);

                System.out.println("Valid");

            }catch(PatternSyntaxException ex){

                System.out.println("Invalid");

            }

        }

    }

}

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