ValidParanthesis.java

import java.util.*;
public class ValidParanthesis {
    public static boolean validparanthesis(String str){
        Stack<Character> s = new Stack<>();
        for(int i=0;i<str.length();i++){
            char ch = str.charAt(i);
            if (ch=='('||ch=='{'||ch=='['){
                s.push(ch);
            }else{
                if (s.isEmpty()){
                    return false;
                }else{
                    if ((ch==')' && s.peek()=='(') ||
                    (ch=='}' && s.peek()=='{') ||
                    (ch==']' && s.peek()=='[')) {
                        s.pop();
                    }else{
                        return false;
                    }
                }
            }
        }
        if (s.isEmpty()){
            return true;
        }
        return false;
    }
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter the string: ");
        String str = sc.nextLine();
        System.out.println(validparanthesis(str));
    }
}