arithmetic.java

一个java 课程设计作业

// Decompiled by Jad v1.5.8g. Copyright 2001 Pavel Kouznetsov.
// Jad home page: http://www.kpdus.com/jad.html
// Decompiler options: packimports(3) ansi 
// Source File Name:   Arithmetic.java

import java.io.PrintStream;

public class Arithmetic
{

    public int addsubt()
    {
        int i = multdiv();
        while(s.charAt(pos) == '+' || s.charAt(pos) == '-') 
        {
            char c = s.charAt(pos++);
            int j = multdiv();
            if(c == '+')
                i += j;
            else
                i -= j;
        }
        return i;
    }

    public int multdiv()
    {
        int i = number();
        while(s.charAt(pos) == '*' || s.charAt(pos) == '/') 
        {
            char c = s.charAt(pos++);
            int j = number();
            if(c == '*')
                i *= j;
            else
                i /= j;
        }
        return i;
    }

    public int number()
    {
        int i = 0;
        if(s.charAt(pos) == '(')
        {
            pos++;
            i = addsubt();
            if(s.charAt(pos++) != ')')
                System.out.print("error");
            return i;
        }
        String s1 = "";
        for(; s.charAt(pos) == '0' || s.charAt(pos) == '1' || s.charAt(pos) == '2' || s.charAt(pos) == '3' || s.charAt(pos) == '4' || s.charAt(pos) == '5' || s.charAt(pos) == '6' || s.charAt(pos) == '7' || s.charAt(pos) == '8' || s.charAt(pos) == '9'; pos++)
            s1 = s1 + Integer.parseInt(Character.toString(s.charAt(pos)));

        i = Integer.parseInt(s1);
        return i;
    }

    public Arithmetic(String s1)
    {
        Arithmetic _tmp = this;
        pos = 0;
        s = s1;
        int i = 0;
        i = addsubt();
        end = String.valueOf(i);
    }

    static int pos;
    String s;
    String end;
}