// Proj4.java

// Date: 3/1/98
// Author: Adam Berger
// Description: 15-212 sample solution to programming project 4. Wrapper for interpreter.

import java.io.*;
import java.math.*;

public class Proj4 {
  public static void main (String args[]) {
    Parser parser = new Parser(System.in);
    BigInteger eval = null;
    try { 
      parser.parse(); 
      if (args.length>0) parser.setInput(args[0]);
      eval = parser.interpret();
    }
    catch (SLException e) { System.out.println(e.getMessage()); return; }
  }
}