package lists;

public class Calculator
{
    public static List tokenize(String s)
    {
        List tokens = new List();
        String number = "";
        
        for (int i = 0; i < s.length(); i++)
        {
            char cc = s.charAt(i);
            
            if (Token.isDigit(cc))
                number += cc;
            else if (Token.isOperator(cc))
            {
                tokens.add(new Token(number));
                tokens.add(new Token(cc));
                number = "";
            }
        }
        tokens.add(new Token(number));
        
        return tokens;
    }
    
    public static List toPostfix(List l)
    {
        List postfix = new List();
        
        return postfix;
    }
    
    public static double evaluate(List postfix)
    {
     
        return 0.0;
    }

    private static void printList(List l)
    {
        l.first();
        while (!l.isLast())
        {
            Token t = (Token)l.get();
            System.out.println("token = " + t);
            l.next();
        }
        Token t = (Token)l.get();
        System.out.println("token = " + t);
    }
    
    public static void main(String args[])
    {
        String input = "10    +304*14-99+88*7";
        List tokens = tokenize(input);
printList(tokens);
        List postfix = toPostfix(tokens);
printList(postfix);        
        double answer = evaluate(postfix);
        System.out.println(input + " = " + answer);
    }
}