## .h

```
#pragma once#include <iostream>
using namespace std;
class Circle { int radius;public: Circle() {  radius = 1;  cout << "create " << radius << endl; } Circle(int r) {  radius = r;  cout << "create " << radius << endl; } double getArea(); void setRadius(int r) {  radius = r; } ~Circle() {  cout << "destroy " << radius << endl; }};
double Circle::getArea() { return 3.14 * radius * radius;}
```

##.c

```
#include "헤더.h"
int main() { Circle donut; Circle pizza(30);
 cout << donut.getArea() << endl;
 Circle *p;
 p = &donut;
 cout << p->getArea() << endl; cout << (*p).getArea() << endl;
 Circle circleArray[3];
 circleArray[0].setRadius(10); circleArray[1].setRadius(20); circleArray[2].setRadius(30);
 int i; for (i = 0; i < 3; i += 1) {  cout << "area: " << i << " " << circleArray[i].getArea() << endl; }
 Circle *pointer; pointer = circleArray;
 for (i = 0; i < 3; i += 1) {  cout << "area: " << i << " " << pointer->getArea() << endl;  pointer++; }
 Circle *pArray = new Circle[3]; pArray[0].setRadius(10); pArray[1].setRadius(20); pArray[2].setRadius(30);
 for (i = 0; i < 3; i += 1) {  //cout << pArray[i].getArea() << endl;  cout << pArray->getArea() << endl;  pArray++;  } pArray = pArray - 3; Circle *pointArray2 = pArray;
 for (i = 0; i < 3; i += 1) {  cout << (pointArray2 + i)->getArea() << endl;  //pointArray2++; }
 delete[] pArray;}
```