import java.util.*;

public class BracketMatchTestProgram {

 public static boolean bracketsMatch(String s) {
     int   count = 0;
     char  c;

     for (int i=0; i<s.length(); i++) {
         c = s.charAt(i);
         if (c == '(') count++;
         if (c == ')') count--;
         if (count < 0)
             return false;
     }
     return count == 0;
 }

 public static boolean bracketsMatch2(String s) {
     Stack<Character> aStack;
     char     c;

     aStack = new Stack<Character>();
     for (int i=0; i<s.length(); i++) {
         c = s.charAt(i);

         if ((c == '(') || (c == '[') || (c == '{'))  // got open bracket
             aStack.push(c);

         if ((c == ')') || (c == ']') || (c == '}')) { // got closed bracket
             if (aStack.isEmpty())
                 return false;  // no open bracket for this closed one

             char top = aStack.pop(); // get the last opening bracket found
             if (((c == ')') && (top != '(')) ||
                 ((c == ']') && (top != '[')) ||
                 ((c == '}') && (top != '{')))
                 return false;  // wrong closing bracket for last opened one
         }
     }
     return aStack.isEmpty();  // No match if brackets are left over
 }

    public static void main(String[] args) {
        Scanner    keyboard = new Scanner(System.in);
        String     aString;

        do {
            System.out.println("Please enter expression: (<cr> to quit)");
            aString = keyboard.nextLine();

            if (bracketsMatch(aString))
                System.out.println("The brackets match");
            else
                System.out.println("The brackets do not match");
        } while (aString.length() > 0);
    }
}