  import java.util.Scanner; 
 
  /** 
     This program calculates the value of an expression 
     consisting of numbers, arithmetic operators, and parentheses. 
  */ 
  public class ExpressionCalculator 
  { 
     public static void main(String[] args) 
    { 
       Scanner in = new Scanner(System.in); 
       System.out.print(Enter an expression: ); 
       String input = in.nextLine(); 
      Evaluator e = new Evaluator(input); 
       int value = e.getExpressionValue(); 
       System.out.println(input + = + value); 
    } 
 } 
