作业

#ifndef CLASS_H
#define CLASS_H
#include <iostream>
using namespace std;
class Rect
{
private:int width;int height;
public:void init(int w,int h);void set_w(int w);void set_h(int h);void show();
};
#endif // CLASS_H

#include "class.h"void Rect::init(int w, int h)
{width=w;height=h;
}void Rect::set_w(int w)
{width=w;
}void Rect::set_h(int h)
{height=h;
}void Rect::show()
{cout << "area=" <<width*height <<endl;cout << "perimeter=" <<width*2+height*2 <<endl;}

#include "class.h"
int main()
{Rect re;re.init(2,4);re.show();re.set_w(4);re.show();re.set_h(5);re.show();return 0;
}