[C#版本]有趣啊！各种编程语言实现 2 + 2 = 5

static void Main (string[] args)
{
    var x = 2;
    var y = 2;

    if (1 == 0) ;
    {
        ++x;
    }

    Console.WriteLine (x + y);
}

static void Main(string[] args)
{
    using (var p = new CSharpCodeProvider())
    {
        Console.SetOut((TextWriter)p.CompileAssemblyFromSource(new CompilerParameters() { GenerateExecutable = false, GenerateInMemory = true, IncludeDebugInformation = false }, "using System.IO;using System.Text;class a:TextWriter{TextWriter _;public a(TextWriter w){_=w;}public override void Write(char v){_.Write(v=='4'?'5':v);} public override Encoding Encoding{get{return _.Encoding;}}}").CompiledAssembly.GetTypes()[0].GetConstructor(new[] { typeof(TextWriter) }).Invoke(new object[] { Console.Out }));
    }

    Console.WriteLine("{0}+{1}={2}", 2, 2, 2 + 2);
}