/** * Exercise on encapsulation and generalization. */ public class Exercise { public static void main(String[] args) { String s = "((3 + 7) * 2)"; int count = 0; for (int i = 0; i < s.length(); i++) { char c = s.charAt(i); if (c == '(') { count++; } else if (c == ')') { count--; } } System.out.println(count); } }