c++ namespace 활용 및 구조체 내의 함수 예시 , 열혈c++ Chapter 03 문제 03-1

namespace 활용

#include <iostream>
using namespace std;

namespace CAR_CONST
{
	enum
	{
		ID_LEN = 20,
		MAX_SPD = 200,
		FUEL_STEP = 2,
		ACC_STEP = 10,
		BRK_STEP = 10
	};
}

struct Car
{
	char gamerID[CAR_CONST::ID_LEN];
	int fuelGauge;
	int curSpeed;


	void ShowCarState()
	{
		cout << "소유자ID: " << gamerID << endl;
		cout << "연료량: " << fuelGauge << "%" << endl;
		cout << "현재속도:" << curSpeed << "km/s" << endl << endl;
	}

	void Accel()
	{
		if (fuelGauge <= 0)
			return;
		else
			fuelGauge -= CAR_CONST::FUEL_STEP;

		if (curSpeed + CAR_CONST::ACC_STEP >= CAR_CONST::MAX_SPD)
		{
			curSpeed = CAR_CONST::MAX_SPD;
			return;
		}
		curSpeed += CAR_CONST::ACC_STEP;
	}


	void Break()
	{
		if (curSpeed < CAR_CONST::BRK_STEP)
		{
			curSpeed = 0;
			return;
		}
		curSpeed -= CAR_CONST::BRK_STEP;
	}
};

int main()
{
	Car run99 = { "run99",100,0 };
	run99.Accel();
	run99.Accel();
	run99.ShowCarState();
	run99.Break();
	run99.ShowCarState();

	Car sped77 = { "sped77",100,0 };
	sped77.Accel();
	sped77.Break();
	sped77.ShowCarState();

	return 0;
}

구조체내의 함수 예제

#include <iostream>
using namespace std;

#define ID_LEN	20
#define MAX_SPD 200
#define FUEL_STEP 2
#define ACC_STEP 10
#define BRK_STEP 10

struct Car
{
	char gamerID[ID_LEN];
	int fuelGauge;
	int curSpeed;


	void ShowCarState()	
	{
		cout << "소유자ID: " << gamerID << endl;
		cout << "연료량: " << fuelGauge << "%" << endl;
		cout << "현재속도:" <<curSpeed << "km/s" << endl << endl;
	}

	void Accel()	
	{
		if (fuelGauge <= 0)
			return;		
		else
			fuelGauge -= FUEL_STEP;

		if (curSpeed + ACC_STEP >= MAX_SPD)
		{
			curSpeed = MAX_SPD;
			return;
		}
		curSpeed += ACC_STEP;
	}


	void Break()
	{
		if (curSpeed < BRK_STEP)
		{
			curSpeed = 0;
			return;
		}
		curSpeed -= BRK_STEP;
	}
};

int main()
{
	Car run99 = { "run99",100,0 };
	run99.Accel();
	run99.Accel();
	run99.ShowCarState();
	run99.Break();
	run99.ShowCarState();

	Car sped77 = { "sped77",100,0 };
	sped77.Accel();
	sped77.Break();
	sped77.ShowCarState();

	return 0;
}

Chapter3 문제 03-1

#define _CRT_SECURE_NO_WANRINGS
#include <iostream>
using namespace std;

struct Point
{
	int xpos;
	int ypos;

	void MovePos(int x, int y)
	{
		xpos += x;
		ypos += y;
	}

	void AddPoint(const Point& pos)
	{
		xpos += pos.xpos;
		ypos += pos.ypos;
	}

	void ShowPosition()
	{
		cout << "[" << xpos << "," << ypos << "]" << endl;
	}

};
int main()
{
	Point pos1 = { 12,4 };
	Point pos2 = { 20,30 };

	pos1.MovePos(-7, 10);
	pos1.ShowPosition();

	pos1.AddPoint(pos2);
	pos1.ShowPosition();
	return 0;
}
​