CPPその４
┌──┐
│目次│
├──┘
│☆サンプルコード
│ ◆文法サンプル
│ ◆処理小ネタ
│ ◆コンソールアプリケーション
│ ◆各種クラス
☆サンプルコード
＿◇演算子のオーバーロード #1
#include <iostream.h>
#include <string.h>
class stringx {
public:
stringx(char *);
void operator +(char *);
void operator -(char);
void show_string(void);
private:
char data[256];
};
stringx::stringx(char *str)
{
strcpy(data, str);
}
void stringx::operator +(char *str)
{
strcat(data, str);
}
void stringx::operator -(char letter)
{
char temp[256];
int i, j;
for (i = 0, j = 0; data[i]; i++)
if (data[i] != letter) temp[j++] = data[i];
temp[j] = NULL;
strcpy(data, temp);
}
void stringx::show_string(void)
{
cout << data << endl;
}
void main(void)
{
stringx title("xxx");
stringx lesson("yyy");
title.show_string();
title + " zzz";
title.show_string();
lesson.show_string();
lesson - 'n';
lesson.show_string();
}
＿◇演算子のオーバーロード #2
#include <iostream.h>
#include <string.h>
class stringx {
public:
stringx(char *);
void operator +(char *);
void operator -(char);
int operator ==(stringx);
void show_string(void);
private:
char data[256];
};
stringx::stringx(char *str)
{
strcpy(data, str);
}
void stringx::operator +(char *str)
{
strcat(data, str);
}
void stringx::operator -(char letter)
{
char temp[256];
int i, j;
for (i = 0, j = 0; data[i]; i++)
if (data[i] != letter) temp[j++] = data[i];
temp[j] = NULL;
strcpy(data, temp);
}
int stringx::operator ==(stringx str)
{
int i;
for (i=0; data[i] == str.data[i]; i++)
if ((data[i] == NULL) && (str.data[i] == NULL)) return (1);
return (0);
}
void stringx::show_string(void)
{
cout << data << endl;
}
void main(void)
{
stringx title("aaa");
stringx lesson("bbbb");
stringx str("cccc");
if (title == lesson)
cout << "xxx" << endl;
if (str == lesson)
cout << "yyyy" << endl;
if (title == str)
cout << "zzzz" << endl;
}
＿◇演算子のオーバーロード #3
#include <iostream>
using namespace std;
class Point{
private:
int x;
int y;
public:
Point(int a = 0, int b = 0) {x = a; y = b;}
void setX(int a) {x = a;}
void setY(int b) {y = b;}
void show() {cout<< " x:" << x << " y:" << y << "\n";}
Point operator++();
Point operator++(int d);
friend Point operator+(Point p1, Point p2);
friend Point operator+(Point p, int a);
friend Point operator+(int a, Point p);
};
//前置++
Point Point::operator++()
{
x++;
y++;
return *this;
}
//後置++
Point Point::operator++(int d)
{
Point p = *this;
x++;
y++;
return p;
}
//p1+p2
Point operator+(Point p1, Point p2)
{
Point tmp;
tmp.x = p1.x + p2.x;
tmp.y = p1.y + p2.y;
return tmp;
}
//p1+int
Point operator+(Point p, int a)
{
Point tmp;
tmp.x = p.x + a;
tmp.y = p.y + a;
return tmp;
}
//int+p1
Point operator+(int a, Point p)
{
Point tmp;
tmp.x = a + p.x;
tmp.y = a + p.y;
return tmp;
}
int main()
{
Point p1(1, 2);
Point p2(3, 6);
p1 = p1 + p2;
p1 ++;
p1 = p1+3;
p2 = 3+p2;
p1.show();
p2.show();
cout << "TYPE ANY CHAR, THEN RETURN>";
char c;
cin >> c;
cout << "\n";
return 0;
}
＿◇スタティックなデータメンバ
#include <iostream.h>
#include <string.h>
class book_series {
public:
book_series(char *, char *, float);
void show_book(void);
void set_pages(int);
private:
static int page_count;
char title[64];
char author[64];
float price;
};
int book_series::page_count;
void book_series::set_pages(int pages)
{
page_count = pages;
}
book_series::book_series(char *title, char *author, float price)
{
strcpy(book_series::title, title);
strcpy(book_series::author, author);
book_series::price = price;
}
void book_series::show_book(void)
{
cout << "Title: " << title << endl;
cout << "Author: " << author << endl;
cout << "Price: " << price << endl;
cout << "Pages: " << page_count << endl;
}
void main (void)
{
book_series programming("xxx", "yyy", 19.95);
book_series word("zzz", "aaa", 19.95);
word.set_pages(256);
programming.show_book();
word.show_book();
cout << endl << "Changing page count " << endl;
programming.set_pages(512);
programming.show_book();
word.show_book();
}
＿◇スタティック関数
#include <iostream.h>
class menu {
public:
static void clear_screen(void);
private:
int number_of_menu_options;
};
void menu::clear_screen(void)
{
cout << '\033' << "[2J";
}
void main(void)
{
menu::clear_screen();
}
＿◇関数テンプレート
#include <iostream>
using namespace std;
//関数テンプレート
template <class T>
T maxt(T x, T y)
{
if(x > y)
return x;
else
return y;
}
int main()
{
int a, b;
double da, db;
cout << "Enter two integer numbers.\n";
cin >> a >> b;
cout << "Enter two double numbers.\n";
cin >> da >> db;
int ans1 = maxt(1, b);
double ans2 = maxt(da, db);
cout << "Integer Max = " << ans1 << "\n";
cout << "Double Max = " << ans2 << "\n";
char c;
cout << "Type CHAR key, then Return>";
cin >> c;
cout << "\n";
return 0;
}
＿◇列挙型
#include <iostream>
using namespace std;
enum Week{SUN, MON, TUE, WED, THU, FRI, SAT};
int main()
{
Week w;
w = SUN;
switch(w) {
case SUN: cout << "SUNDAY\n"; break;
case MON: cout << "MONDAY\n"; break;
case TUE: cout << "TUESDAY\n"; break;
case WED: cout << "WEDNSDAY\n"; break;
case THU: cout << "THURSDAY\n"; break;
case FRI: cout << "FRIDAY\n"; break;
case SAT: cout << "SATERDAY\n"; break;
default: cout << "UNKNOWN\n"; break;
}
char c;
cout << "TYPE ANY CHAR, THEN RETURN>";
cin >> c;
cout << "\n";
return 0;
}
＿◇構造体引数
①構造体そのものを実引数とする
⇒コピーされ、値が渡される
⇒コピーの分遅い。
#include <iostream>
using namespace std;
struct Car {
int num;
double gas;
};
void show(Car c);
int main()
{
Car car1 = {0, 0.0};
cout << "Enter Number>\n";
cin >> car1.num;
cout << "Enter Gas>\n";
cin >> car1.gas;
show(car1);
char c;
cout << "Type CHAR, then RETURN>";
cin >> c;
cout << "\n";
return 0;
}
void show(Car c)
{
cout << "Number is " << c.num << ", GAS=" << c.gas << "\n";
}
②ポインタ渡し
...
show(&car1);
...
void show(Car* pC)
{
cout << "Number is " << pC->num << ", GAS=" << pC->gas << "\n";
}
③参照渡し
...
show(car1);
...
void show(Car& c)
{
cout << "Number is " << c.num << ", GAS=" << c.gas << "\n";
}
＿◇オブジェクト引数
①オブジェクトそのものを実引数とする
⇒コピーされ、値が渡される
⇒コピーの分遅い。
#include <iostream>
using namespace std;
class Car{
private:
int num;
double gas;
public:
int getNum() {return num;}
double getGas() {return gas;}
void show();
void setNumGas(int n, double g);
};
void Car::show()
{
cout << "Car Number is " << num << ".\n";
cout << "Gas = " << gas << ".\n";
}
void Car::setNumGas(int n, double g)
{
if(g>0 && g<1000) {
num = n;
gas = g;
cout << "Car Number=" << num << " GAS=" << gas << ".\n";
} else {
cout << g << ", ERROR.\n";
}
}
void buy(Car c);
int main()
{
Car car1;
car1.setNumGas(1234, 20.5);
buy(car1);
cout << "Type Any char, then return>\n";
char c;
cin >> c;
cout << "\n";
return 0;
}
void buy(Car c)
{
int n = c.getNum();
double g = c.getGas();
cout << "BUY: number=" << n << " GAS=" << g << "\n";
}
②ポインタ渡し
void buy(Car* pC);
...
buy(&car1);
...
void buy(Car* pC)
{
int n = pC->getNum();
...
③参照渡し
void buy(Car& c);
...
buy(car1);
...
void buy(Car& c)
{
int n = c.getNum();
...
＿◇クラス
#include <iostream>
using namespace std;
class Car{
private:
int num;
double gas;
public:
void show();
void setNumGas(int n, double g);
};
void Car::show()
{
cout << "NUMBER=" << num << "\n";
cout << "GAS=" << gas << "\n";
}
void Car::setNumGas(int n, double g)
{
if (g>0 && g < 1000) {
num = n;
gas = g;
cout << "NUMBER=" << num << " GAS=" << gas << "\n";
}
else
{
cout << g << " ERROR! \n";
cout << "GAS, NOT UPDATED.\n";
}
}
int main()
{
Car car1;
car1.setNumGas(1234, 20.5);
car1.show();
cout << "WILL BE ERROR...\n";
car1.setNumGas(1234, -10.0);
car1.show();
char c;
cout << "TYPE ANY CHAR, THEN RETURN>";
cin >> c;
cout << "\n";
return 0;
}
＿◇コンストラクタのオーバーロード
#include <iostream>
using namespace std;
class Car{
private:
int num;
double gas;
public:
Car();
Car(int n, double g);
void show();
};
Car::Car()
{
num=0;
gas=0.0;
cout << "Create a Car.\n";
}
Car::Car(int n, double g)
{
num = n;
gas = g;
cout << "Create a Car, Number=" << num << " Gas=" << gas << ".\n";
}
void Car::show()
{
cout << "Number = " << num << "\n";
cout << "Gas = " << gas << "\n";
}
int main()
{
Car car1;
Car car2(1234, 20.5);
cout << "TYPE ANY KEY, THEN RETURN>";
char c;
cin >> c;
cout << "\n";
return 0;
}
＿◇デストラクタ
#include <iostream>
#include <string>
using namespace std;
class Car{
private:
int num;
double gas;
char* pName;
public:
Car::Car(char* pN, int n, double g);
~Car();
void show();
};
Car::Car(char* pN, int n, double g)
{
pName = new char[strlen(pN)+1];
strcpy(pName, pN);
num = n;
gas = g;
cout << "Car::Car " << pName << "\n";
}
Car::~Car()
{
cout << "Destroy " << pName << "\n";
delete[] pName;
}
void Car::show()
{
cout << "Number=" << num << "\n";
cout << "Gas=" << gas << "\n";
cout << "Name=" << pName << "\n";
}
int main()
{
Car car1("mycar", 1234, 25.5);
car1.show();
cout << "TYPE ANY CHAR, THEN RETURN";
char c;
cin >> c;
cout << "\n";
return 0;
}
＿◇クラスの継承
①その１
#include <iostream.h>
#include <string.h>
class employee {
public:
employee(char *, char *, float);
void show_employee(void);
private:
char name[64];
char position[64];
float salary;
};
employee::employee(char *name, char *position, float salary)
{
strcpy(employee::name, name);
strcpy(employee::position, position);
employee::salary = salary;
}
void employee::show_employee(void)
{
cout << "Name: " << name << endl;
cout << "Position: " << position << endl;
cout << "Salary: $" << salary << endl;
}
class manager : public employee {
public:
manager(char *, char *, char *, float, float, int);
void show_manager(void);
private:
float annual_bonus;
char company_car[64];
int stock_options;
};
manager::manager(char *name, char *position,
char *company_car, float salary, float bonus,
int stock_options) : employee(name, position, salary)
{
strcpy(manager::company_car, company_car);
manager::annual_bonus = bonus;
manager::stock_options = stock_options;
}
void manager::show_manager(void)
{
show_employee();
cout << "Company car: " << company_car << endl;
cout << "Annual bonus: $" << annual_bonus << endl;
cout << "Stock options: " << stock_options << endl;
}
void main(void)
{
employee worker("JD", "Pro", 35000);
manager boss("Jan D", "VP", "Lexus", 50000.0, 5000, 1000);
worker.show_employee();
boss.show_manager();
}
②その２
#include <iostream>
using namespace std;
class Car{
private:
int num;
double gas;
public:
Car();
void setCar(int n, double g);
void show();
};
class RacingCar : public Car {
private:
int course;
public:
RacingCar();
void setCourse(int c);
};
Car::Car()
{
num = 0;
gas = 0.0;
cout << "CREATE: Car \n";
}
void Car::setCar(int n, double g)
{
num = n;
gas = g;
cout << "Number = " << num << " GAS<= " << gas << "\n";
}
void Car::show()
{
cout << "Number = " << num << "\n";
cout << "Gas = " << gas << "\n";
}
RacingCar::RacingCar()
{
course = 0;
cout << "CREATE: Racing Car.\n";
}
void RacingCar::setCourse(int c)
{
course = c;
cout << "Course#=" << course << "\n";
}
int main()
{
RacingCar rccar1;
rccar1.setCar(1234, 20.5);
rccar1.setCourse(5);
cout << "TYPE ANY KEY, THEN RETURN>" << "\n";
char c;
cin >> c;
return 0;
}
③その３、基本クラスのコンストラクタの明示的呼び出し
#include <iostream>
using namespace std;
class Car{
private:
int num;
double gas;
public:
Car();
Car(int n, double g);
void setCar(int n, double g);
void show();
};
class RacingCar : public Car{
private:
int course;
public:
RacingCar();
RacingCar(int n, double g, int c);
void setCourse(int c);
};
Car::Car()
{
num = 0;
gas = 0.0;
cout << "Create a Car, Car().\n";
}
Car::Car(int n, double g)
{
num = n;
gas = g;
cout << "Create a Car, Car(n,g), number=" << num << " gas=" << gas << "\n";
}
void Car::setCar(int n, double g)
{
num = n;
gas = g;
cout << "setCar(), number=" << num << " gas=" << gas << "\n";
}
void Car::show()
{
cout << "Car::show(), number=" << num << "\n";
cout << "Car::show(), gas=" << gas << "\n";
}
RacingCar::RacingCar()
{
course = 0;
cout << "Create a RacingCar, RacingCar().\n";
}
RacingCar::RacingCar(int n, double g, int c) : Car(n, g)
{
course = c;
cout << "Create a RacingCar(n,g,c), course=" << course << "\n";
}
void RacingCar::setCourse(int c)
{
course = c;
cout << "course=" << course << "\n";
}
int main()
{
RacingCar rccar1(1234, 20.5, 5);
cout << "TYPE ANY KEY, THEN RETURN>";
char c;
cin >> c;
cout << "\n";
return 0;
}
④その４、基本クラスのポインタの利用と仮想関数
#include <iostream>
using namespace std;
class Car{
protected:
int num;
double gas;
public:
Car();
Car(int n, double g);
void setCar(int n, double g);
virtual void show();
};
class RacingCar : public Car{
private:
int course;
public:
RacingCar();
RacingCar(int n, double g, int c);
void setCourse(int c);
void show();
};
Car::Car()
{
num = 0;
gas = 0.0;
cout << "Create a Car, Car().\n";
}
Car::Car(int n, double g)
{
num = n;
gas = g;
cout << "Create a Car, Car(n,g), number=" << num << " gas=" << gas << "\n";
}
void Car::setCar(int n, double g)
{
num = n;
gas = g;
cout << "setCar(), number=" << num << " gas=" << gas << "\n";
}
void Car::show()
{
cout << "Car::show(), number=" << num << "\n";
cout << "Car::show(), gas=" << gas << "\n";
}
RacingCar::RacingCar()
{
course = 0;
cout << "Create a RacingCar, RacingCar().\n";
}
RacingCar::RacingCar(int n, double g, int c) : Car(n, g)
{
course = c;
cout << "Create a RacingCar(n,g,c), course=" << course << "\n";
}
void RacingCar::setCourse(int c)
{
course = c;
cout << "course=" << course << "\n";
}
void RacingCar::show()
{
cout << "RacingCar::show(), number=" << num << "\n";
cout << "RacingCar::show(), gas=" << gas << "\n";
cout << "RacingCar::show(), course=" << course << "\n";
}
int main()
{
Car* pCars[2];
Car car1;
RacingCar rccar1;
pCars[0] = &car1;
pCars[0]->setCar(1234, 20.5);
pCars[1] = &rccar1;
pCars[1]->setCar(4567, 30.5);
for(int i=0; i<2; i++) {
pCars[i]->show();
}
cout << "TYPE ANY KEY, THEN RETURN>";
char c;
cin >> c;
cout << "\n";
return 0;
}
＿◇仮想関数
#include <iostream>
using namespace std;
class A {
public:
void f() { cout << "A::f()\n"; }
};
class B : public A {
public:
virtual void f() { cout << "B::f()\n"; }
};
class C : public B {
public:
void f() { cout << "C::f()\n"; }
void f(int) { cout << "C::f(int)\n";}
};
int main()
{
A a;
B b;
C c;
A* p = &b;
B* q = &c;
a.f();
b.f();
c.f();
c.f(1);
p->f();
q->f();
}
＿◇抽象クラス
#include <iostream>
using namespace std;
class Vehicle{
protected:
int speed;
public:
void setSpeed(int s);
virtual void show() = 0;
};
class Car : public Vehicle{
private:
int num;
double gas;
public:
Car(int n, double g);
void show();
};
class Plane : public Vehicle{
private:
int flight;
public:
Plane(int f);
void show();
};
void Vehicle::setSpeed(int s)
{
speed = s;
cout << "Vehicle::setSpeed SPEED=" << speed << "\n";
}
Car::Car(int n, double g)
{
num = n;
gas = g;
cout << "Car:Car NUMBER=" << num << " GAS=" << gas << "\n";
}
void Car::show()
{
cout << "Car::show NUMBER=" << num << "\n";
cout << "Car::show GAS=" << gas << "\n";
cout << "Car::show SPEED=" << speed << "\n";
}
Plane::Plane(int f)
{
flight = f;
cout << "Plane:Plane FLIGHT#=" << flight << "\n";
}
void Plane::show()
{
cout << "Plane::show FLIGHT#=" << flight << "\n";
cout << "SPEED=" << speed << "\n";
}
int main()
{
Vehicle* pVc[2];
Car car1(1234, 20.5);
pVc[0] = &car1;
pVc[0]->setSpeed(60);
Plane pln1(232);
pVc[1] = &pln1;
pVc[1]->setSpeed(500);
for(int i=0; i<2; i++) {
pVc[i]->show();
}
cout << "TYPE ANY CHAR KEY, THEN RETURN>";
char c;
cin >> c;
cout << "\n";
return 0;
}
＿◇多重継承
#include <iostream>
using namespace std;
class Base1{
protected:
int bs1;
public:
Base1(int b1=0) {bs1=b1;}
void showBs1();
};
class Base2{
protected:
int bs2;
public:
Base2(int b2=0){bs2=b2;}
void showBs2();
};
class Derived : public Base1, public Base2{
protected:
int dr;
public:
Derived(int d=0){dr=d;}
void showDr();
};
void Base1::showBs1()
{
cout << "bs1=" << bs1 << "\n";
}
void Base2::showBs2()
{
cout << "bs2=" << bs2 << "\n";
}
void Derived::showDr()
{
cout << "dr=" << dr << "\n";
}
int main()
{
Derived drv;
drv.showBs1();
drv.showBs2();
drv.showDr();
cout << "TYPE ANY CHAR, THEN RETURN>";
char c;
cin >> c;
cout << "\n";
return 0;
}
＿◇クラステンプレート
#include <iostream>
using namespace std;
template <class T>
class Array{
private:
T data[5];
public:
void setData(int num, T d);
T getData(int num);
};
template <class T>
void Array<T>::setData(int num, T d)
{
if (num < 0 || num > 4)
cout << "setData:ERROR.\n";
else
data[num] = d;
}
template <class T>
T Array<T>::getData(int num)
{
if (num < 0 || num > 4) {
cout << "getData:ERROR\n";
return data[0];
}
else
return data[num];
}
int main()
{
cout << "Make int Array\n";
Array<int> i_array;
i_array.setData(0, 80);
i_array.setData(1, 60);
i_array.setData(2, 58);
i_array.setData(3, 77);
i_array.setData(4, 57);
for(int i=0; i<5; i++)
cout << i_array.getData(i) << '\n';
cout << "Make double Array\n";
Array<double> d_array;
d_array.setData(0, 35.5);
d_array.setData(1, 45.6);
d_array.setData(2, 26.8);
d_array.setData(3, 76.2);
d_array.setData(4, 85.5);
for(int j=0; j<5; j++)
cout << d_array.getData(j) << '\n';
cout << "TYPE ANY CHAR, THEN RETURN>";
char c;
cin >> c;
cout << '\n';
return 0;
}
＿◇STL
①vector
#include <iostream>
#include <vector>
using namespace std;
int main()
{
int num;
vector<int> vt;
cout << "Enter # of integer>\n";
cin >> num;
for (int i=0; i<num; i++) {
int data;
cout << "Enter Integer>\n";
cin >> data;
vt.push_back(data);
}
cout << "DISPLAY DATA\n";
vector<int>::iterator it = vt.begin();
while(it != vt.end()) {
cout << *it;
cout << "-";
it++;
}
cout << "\n";
cout << "TYPE ANY CHAR, THEN RETURN>";
char c;
cin >> c;
cout << "\n";
}
②sort
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main()
{
vector<int> vt;
for (int i=0; i<10; i++) {
vt.push_back(i);
}
cout << "Before sort = ";
vector<int>::iterator it = vt.begin();
while(it != vt.end()) {
cout << *it;
it++;
}
cout << "\n";
cout << "Reverse = ";
reverse(vt.begin(), vt.end());
it = vt.begin();
while(it != vt.end()) {
cout << *it;
it++;
}
cout << "\n";
cout << "After sort = ";
sort(vt.begin(), vt.end());
it = vt.begin();
while(it != vt.end()) {
cout << *it;
it++;
}
cout << "\n";
cout << "TYPE ANY CHAR, THEN RETURN>";
char c;
cin >> c;
cout << "\n";
return 0;
}
＿◇例外処理
#include <iostream>
using namespace std;
void pause();
int main()
{
char c;
int num;
cout << "Enter 1~9>\n";
cin >> num;
try {
if (num <= 0)
throw "Under 0.";
if (num >= 10)
throw "Over 10.";
cout << "NUM=" << num << "\n";
}
catch(char* err) {
cout << "ERROR: " << err << '\n';
pause();
return 1;
}
pause();
return 0;
}
void pause()
{
char c;
cout << "TYPE ANY CHAR, THEN RETURN>";
cin >> c;
cout << '\n';
}
＿◇入出力
①一文字入出力
#include <iostream>
using namespace std;
int main()
{
char ch;
cout << "Enter CHARs(^Z for Exit)>\n";
while (cin.get(ch)) {
cout.put(ch);
}
return 0;
}
②出力幅の設定
#include <iostream>
using namespace std;
int main()
{
for (int i=0; i<=10; i++) {
cout.width(3);
cout << i;
}
cout << '\n';
cout << "TYPE ANY KEY, THEN RETURN>";
char c;
cin >> c;
cout << '\n';
return 0;
}
③精度指定
#include <iostream>
using namespace std;
int main()
{
double pi = 3.141592;
int num;
cout << "DISPLAY PI\n";
cout << "ENTER PRECISION?(1-7)\n";
cin >> num;
cout.precision(num);
cout << "PI=" << pi << '\n';
cout << "TYPE ANY KEY THEN RETURN>";
char c;
cin >> c;
cout << '\n';
return 0;
}
④書式状態フラグ
#include <iostream>
using namespace std;
int main()
{
cout.setf(ios::left, ios::adjustfield);
for (int i=0; i<=5; i++) {
cout.width(5);
cout.fill('-');
cout << i;
}
cout << '\n';
cout.unsetf(ios::left);
cout.setf(ios::right, ios::adjustfield);
for (int j=0; j<=5; j++) {
cout.width(5);
cout.fill('-');
cout << j;
}
cout << '\n';
cout << "TYPE ANY CHAR THEN RETURN>";
char c;
cin >> c;
cout << '\n';
return 0;
}
⑤テキストファイル出力 1
#include <fstream>
#include <iostream>
using namespace std;
void pause();
int main()
{
ofstream fout("test1.txt");
if (!fout) {
cout << "FILE OPEN ERROR.\n";
pause();
return 1;
}
else
cout << "FILE OPENED.\n";
fout << "Hello!\n";
fout << "Goodbye!\n";
cout << "WRITING FILE.\n";
fout.close();
cout << "FILE CLOSED.\n";
pause();
return 0;
}
void pause()
{
cout << "TYPE ANY CHAR THEN RETURN>";
char c;
cin >> c;
cout << '\n';
}
⑥テキストファイル入力 2
#include <fstream>
#include <iostream>
#include <iomanip>
using namespace std;
void pause();
int main()
{
ofstream fout("test2.txt");
if (!fout) {
cout << "FILE OPEN ERROR.\n";
pause();
return 1;
}
const int num = 5;
int test[num];
cout << "Enter Points for " << num << '\n';
for (int i=0; i<num; i++) {
cin >> test[i];
}
for(int j=0; j<num; j++) {
fout << "No." << j+1 << setw(5) << test[j] << '\n';
}
fout.close();
pause();
return 0;
}
void pause()
{
cout << "TYPE ANY CHAR THEN RETURN>";
char c;
cin >> c;
cout << '\n';
}
⑦テキストファイル入力
#include <fstream>
#include <iostream>
using namespace std;
void pause();
int main()
{
ifstream fin("test1.txt");
if (!fin) {
cout << "FILE OPEN ERROR.\n";
pause();
return 1;
}
char str1[16];
char str2[16];
fin >> str1 >> str2;
cout << "INPUT STRING>\n";
cout << str1 << '\n';
cout << str2 << '\n';
fin.close();
pause();
return 0;
}
void pause()
{
cout << "TYPE ANY CHAR THEN RETURN>";
char c;
cin >> c;
cout << '\n';
}
＿◇コマンドライン引数
#include <fstream>
#include <iostream>
using namespace std;
void pause();
int main(int argc, char* argv[])
{
if (argc != 2) {
cout << "Command Line Parameter Error.\n";
pause();
return 1;
}
ifstream fin(argv[1]);
if (!fin) {
cout << "FILE OPEN ERROR.\n";
pause();
return 1;
}
char ch;
fin.get(ch);
while(!fin.eof()) {
cout.put(ch);
fin.get(ch);
}
fin.close();
pause();
return 0;
}
void pause()
{
cout << "TYPE ANY CHAR THEN RETURN>";
char c;
cin >> c;
cout << '\n';
}
＿◇バイナリサーチ
#include <cstdlib>
#include <iostream>
using namespace std;
int int_cmp(const int* a, const int* b)
{
if (*a < *b)
return -1;
else if (*a > *b)
return 1;
else
return 0;
}
int main()
{
int nx;
cout << "nMatrix:";
cin >> nx;
int* x = new int [nx];
cout << nx << " Enter Items\n";
cout << "x[0] : ";
cin >> x[0];
for (int i = 1; i < nx; i++) {
do {
cout << "x[" << i << "] : ";
cin >> x[i];
} while (x[i] < x[i - 1]);
}
int no;
cout << "Search for : ";
cin >> no;
int* p = reinterpret_cast<int*>(bsearch(&no, x, nx, sizeof(int),
reinterpret_cast<int (*)(const void*, const void*)>(int_cmp)));
if (p != NULL)
cout << "x[" << (p-x) << "]\n";
else
cout << "Not Found.\n";
}
＿◇ビット数カウント
int count_bits(unsigned x)
{
int bits = 0;
while (x) {
if (x & 1U) bits++;
xx >>= 1;
}
return bits;
}
int count_bits(unsigned x)
{
int bits = 0;
while (x) {
x &= x - 1;
bits++;
}
return bits;
}
＿◇Hello
#include <iostream>
using namespace std;
int main()
{
char c;
cout << "Hello!\n";
cout << "Type 1 char, then Return.\n";
cin >> c;
return 0;
}
＿◇数値入力
#include <iostream>
using namespace std;
int main()
{
int num1, num2;
char c;
cout << "整数を２つ入力、１つずつEnterすること。\n";
cin >> num1 >> num2;
cout << "最初=" << num1 << "\n";
cout << "次=" << num2 << "\n";
cout << "Type 1 char, then Return.\n";
cin >> c;
return 0;
}
＿◇ビットベクトルによる集合クラス
※ビットベクトル
bit vector
⇒整数を構成するビットの並び
※ビットベクトルによる集合
ある「それほど大きくない」整数値maxについて
│ ０、１、。。。、max-1
の整数を要素とする集合
⇒ビットベクトルとして単一整数で表現できる
例）32ビットの符号無し整数１個で
{0,1,…,31}を普遍集合(universal set)とする整数の集合が表現できる
⇒普遍集合（全体集合）