import java.util.*;

public class ParenBalancing3 {

    public static void main (String[] argv)
    {
	// Test 1.
	String s = "([()])";
	checkParens (s);

	// Test 2.
	s = "[][()]()";
	checkParens (s);

	// Test 3.
	s = "((())]";
	checkParens (s);

	// Test 4.
	s = "[)(]";
	checkParens (s);
    }


    static void checkParens (String inputStr)
    {
	char[] letters = inputStr.toCharArray();
	Stack<Character> stack = new Stack<Character> ();

	boolean unbalanced = false;

	for (int i=0; i<letters.length; i++) {

	    if ( (letters[i] == '(') || (letters[i] == '[') ) {
		// Push every left paren of each kind.
		stack.push (letters[i]);
	    }
	    else if (letters[i] == ')') {
		// We should have a '(' match on the stack
		char ch = ')';
		if (! stack.isEmpty() ) {
		    ch = stack.pop ();
		}
		if (ch != '(') {
		    // Not matched => unbalanced.
		    unbalanced = true;
		    break;
		}
	    }
	    else if (letters[i] == ']') {
		// We should have a '[' match on the stack
		char ch = ']';
		if (! stack.isEmpty() ) {
		    ch = stack.pop ();
		}
		if (ch != '[') {
		    // Not matched.
		    unbalanced = true;
		    break;
		}
	    }

	} // end-for
	
	if ( (unbalanced) || (! stack.isEmpty()) ) {
	    System.out.println ("String " + inputStr + " has unbalanced parens");
	}
	else {
	    System.out.println ("String " + inputStr + " has balanced parens");	
	}
    }

}