validParenthese.java

import java.util.Stack;

public class validParenthese {

    public static boolean isValid(String s){
        Stack<Character> stack = new Stack<>();
        for(char c : s.toCharArray()){
            if(c == '(' || c == '{' || c == '[')
                stack.push(c);
            else{
                if(stack.isEmpty())
                    return false;
                
                else{
                    char top = stack.peek();
                    if((c == ')' && top == '(') ||
                       (c == '}' && top == '{') ||
                       (c == ']' && top == '['))
                            stack.pop();
                    
                    else
                        return false;
                }
            }
        }

        return stack.isEmpty();

    }

    public static void main(String[] args) {
        String s ="[{()}]";
        System.out.println(isValid(s));

    }
    
}