使用匿名类型和IComparable接口查找文件夹中最大的文件

在执行时，代码出现错误，我不知道在哪里必须进行更改才能实现接口。下面是我在控制台应用程序中尝试的完整代码

  Error 1   'ConsoleApplication16.Temp' does not implement interface member 'System.IComparable<ConsoleApplication16.Temp>.CompareTo(ConsoleApplication16.Temp)'    D:'nnn'ConsoleApplication16'ConsoleApplication16'Program.cs 32  18  ConsoleApplication16

下面是我的代码

class Program
{
    static void Main()
    {
    string []files=Directory.GetFiles("C:''WINDOWS","*.*",SearchOption.AllDirectories);
    Console.WriteLine(files.Count());
   //Get Maximum
   var max = (from fileName in files
                  let info = new FileInfo(fileName)
                  orderby info.Length descending
                  select new { FileName = info.Name, Size = info.Length })
                  .Take(1);
        Console.WriteLine("Using Take : {0}",max.ElementAt(0));
        //With anonymous Type we have to indicate what to get the max of
        var max2 = (from fileName in files
                    let info = new FileInfo(fileName)
                    select
                    new Temp{ FileName = info.Name, Size = info.Length })
                    .Max(s => s.Size);
        Console.WriteLine("Using Max:{0}", max2);
        Console.ReadLine();
    }
}
public class Temp : IComparable<Temp> //error is here
{
    public string FileName { set; get; }
    public long Size { set; get; }
    public int compareTo(Temp o)
    {
        return Size.CompareTo(o.Size);
    }
    public override string ToString()
    {
        return string.Format("FileName:{0},Size:{1}", FileName, Size);
    }
}

public int CompareTo(Temp o)
{
    return Size.CompareTo(o.Size);
}