static void Main(string[] args)
{
//作业:橡皮rubber鸭子、木wood鸭子、真实的鸭子realduck。
//三个鸭子都会游泳，而橡皮鸭子和真实的鸭子都会叫，
//只是叫声不一样，橡皮鸭子“唧唧”叫，真实地鸭子“嘎嘎”叫，木鸭子不会叫.
//IBark bark = new RealDuck();//new XPDuck();
//bark.Bark();
XPDuck xp = new XPDuck();
MuDuck md = new MuDuck();
RealDuck rd = new RealDuck();
IBark bark = rd;
Duck duck = rd;
duck.Swim();
bark.Bark();
Console.ReadKey();
}
public Behavior(IBark bark, IWalk walk)
{
this.bark = bark;
this.walk = walk;
}