4-8
#include <iostream>
using namespace std;
class Dog
{
public:
Dog(int initialAge=0, int initialWeight=5);
~Dog();
int GetAge()
{
return itsAge;
}
void SetAge(int age)
{
itsAge=age;
}
int GetWeight()
{
return itsWeight;
}
void SetWeight(int weight)
{
itsWeight=weight;
}
private:
int itsAge, itsWeight;
};
Dog::Dog(int initialAge, int initialWeight)
{
itsAge=initialAge;
itsWeight=initialWeight;
}
Dog::~Dog()
{
}
int main()
{
Dog Dog1(2,5);//Dog是一个类,再定义变量Dog1
cout<<Dog1.GetAge()<<endl;
cout<<Dog1.GetWeight()<<endl;
Dog1.SetAge(7);
Dog1.SetWeight(10);
cout<<Dog1.GetAge()<<endl;
cout<<Dog1.GetWeight()<<endl;
}
4-9
#include <iostream>
#include <cmath>
using namespace std;
class Rectangle{
public:
int area(int x1,int x2,int y1,int y2);
private:
int x1,y1,x2,y2;};
int Rectangle::area(int x1,int x2,int y1,int y2)
{
int S;
S=(abs(x2-x1))*(abs(y2-y1));
cout<<S<<endl;
}
int main()
{
Rectangle Rectangle1;
int a,b,c,d;
cin>>a>>b>>c>>d;
Rectangle1.area(a,b,c,d);
}
4-10
答案如下图
https://blog.csdn.net/Enterprise_/article/details/79845052
4-11
#include <iostream>
using namespace std;
class Rectangle{
public:
int S(int aa,int hh);
private:
int h, a;
};
int Rectangle::S(int aa,int hh)
{
a=aa;
h=hh;
int s;
s=a*h;
cout<<s<<endl;
}
int main()
{
Rectangle Rectangle1;
int x,y;
cin>>x>>y;
Rectangle1.S(x,y);
}
4-13
#include <iostream>
#include <cmath>
using namespace std;
class Circle{
public:
getArea(int rr);
private:
int radius;};
Circle::getArea(int rr)
{
float area;
radius=rr;
area=3.1415*radius*radius;
cout<<area;
}
int main()
{
Circle Circle1;
int r;
cin>>r;
Circle1.getArea(r);
}
4-14
#include <iostream>
#include <cmath>
using namespace std;
class Tree{
public:
int setage()//函数重载
{
int years;
years=2;
return years;
}
void setage(int aa);
int getage();
private:
int ages;
};
void Tree::setage(int aa)
{
ages=aa+setage();
}
int Tree::getage()
{
return ages;
}
int main()
{
int a;
cin >>a;
Tree tree1;
tree1.setage();
tree1.setage(a);
tree1.getage();
cout<<tree1.getage();
}