java的类继承语法问题
不知道为什么，说这有语法错误，不是eclipse没反应过来的原因。
public class havefun {
father m;
son dd = new son();
bob cc = new bob();
//m = d;
//d = m;
m = dd;
dd = (son)m;
}
class father{
public int a;
}
class son extends father{
public int b;
}
class bob extends father{
public int c;
}
