【原】人生的程序公式

现在我需要下面的公式成立，不许改动，引号都不能加，谁能帮我实现？

if(Me.Today>Me.Yesterday) Me.Tomorrow=Success; else if(Me.Today==Me.Yesterday) Me.Tomorrow=null; else Me.Tomorrow=Failure；

代码如下，请补充，谢谢，【下面代码可以改动】

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
public class Ocean
{
    public string _today, _yesterday, _tomorrow;
    public void MakePlan(string Today, string Yesterday, string Tomorrow)
    {
        _today = Today;
        _tomorrow = Tomorrow;
        _yesterday = Yesterday;
        // Your code goes here
    }
    public string Today
    {
        get
        {
            return _today;
        }
        set
        {
            _today = value;
        }
    }
    public string Tomorrow
    {
        get
        {
            return _tomorrow;
        }
        set
        {
            _tomorrow = value;
        }
    }
    public string Yesterday
    {
        get
        {
            return _yesterday;
        }
        set
        {
            _yesterday = value;
        }
    }
}