Parenthesis/Brackets Matching using Stack algorithm

Question

For example if the parenthesis/brackets is matching in the following:

({})
(()){}()
()

and so on but if the parenthesis/brackets is not mat

Answer 1

import java.util.*;

public class Parenthesis

 {

    public static void main(String...okok)

    {
        Scanner sc= new Scanner(System.in);
        String str=sc.next();
        System.out.println(isValid(str));

    }
    public static int isValid(String a) {
        if(a.length()%2!=0)
        {

            return 0;
        }
        else if(a.length()==0)
        {

            return 1;
        }
        else
        {

            char c[]=a.toCharArray();
            Stack stk =  new Stack();
            for(int i=0;i