定义了一个Date类，然后又定义了一个People类，People类中有一个生日成员，这个生日成员是Date型，那请问输出函数中 People::showPeople怎么输出生日这一项 我是
void People::showPeople(){
    cout<<"编号：    "<<number<<endl;
cout<<"姓名：    "<<name<<endl;
cout<<"性别：    "<<sex<<endl;
cout<<"生日：    "<<birthday<<endl;
cout<<"ID：      "<<id<<endl;
}

应该怎么改正呢？？求指导

用C++的书学C++
而不是用C的书学C++

class Date
{
public:
Date(int y,int m, int d);
private:
int year,month,day;
};
Date::Date(int y; int m; int d)

class Date
{
public:
Date(int y,int m, int d);
private:
int year,month,day;
};
Date::Date(int y; int m; int d)
{
year=y;
month=m;
day=d;
}
class People()
{
public:
People(string str;Date bir)
{
name=str;
birthday=bir(2016,4,49);
}
private：
string name;
Date birthday;
};