import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;
import java.util.Stack;


class MyCode{

    public static void main(String[] args) {

        System.out.println("(a[0]+b[2c[6]]) {24 + 53}  passed:" + parensMatch("(a[0]+b[2c[6]]) {24 + 53}"));
        System.out.println("f(e(d))                    passed:" + parensMatch("f(e(d))"));
        System.out.println("[()]{}([])                 passed:" + parensMatch("[()]{}([])"));
        System.out.println("((b)                       passed:" + !parensMatch("((b)"));
        System.out.println("(c]                        passed:" + !parensMatch("(c]"));
        System.out.println("{(a[])                     passed:" + !parensMatch("{(a[])"));
        System.out.println("([)]                       passed:" + !parensMatch("([)]"));
        System.out.println(")(                         passed:" + !parensMatch(")("));
        System.out.println(" (empty)                   passed:" + parensMatch(""));

    }

    public static boolean parensMatch(String sentence){
	List<Character> expected = new ArrayList<Character>();
		for (Character letter : sentence.toCharArray()){

			if (expected.contains(letter)){
				if (expected.get(expected.lastIndexOf(letter)).equals(expected.get(expected.size()-1)))
						expected.remove(expected.lastIndexOf(letter));
				else break;
			}

			if (letter=='(') expected.add(')');
			else if (letter=='[') expected.add(']');
			else if (letter=='{') expected.add('}');
		}
		return expected.isEmpty();
	}

}