c++类的组合与继承

#include
#include
using namespace std;
class point
{
int x;
int y;
public:
point(int a,int b)
{
x=a;
y=b;
cout<<"基类 point 构造函数被调用"<}
point()
{
}
};
class line:public point
{
point n;
point m;
public:
line(int a,int b,int c,int d):n(a,b),m(c,d)
{
cout<<"派生类 line 构造函数被调用"<}
line()
{
}
int distance(int a,int b,int c,int d)
{
double s;
s=sqrt(1.0*(a-b)*(a-b)+(c-d)*(c-d));
cout<<"线段长为："<return s;
}
};
class rect:public line
{
line q;
line w;
public:
rect(int a,int b,int c,int d,int e,int f,int g,int h):q(a,b,c,d),w(e,f,g,h)
{
cout<<"派生类 rect 构造函数被调用"<}
int perimeter(int a,int b,int c,int d,int e,int f,int g,int h)
{
int sum;
sum=q.distance(a,b,c,d)*2+w.distance(e,f,g,h)*2;
cout<<"周长为："<return sum;
}
int acreage(int a,int b,int c,int d,int e,int f,int g,int h)
{
int product;
product=q.distance(a,b,c,d)*w.distance(e,f,g,h);
cout<<"面积为："<return product;
}
};
int main()
{
rect a1(0,0,0,1,1,1,1,0);
}
只是把你的错误都改掉了