4elist0508.cpp

《21天学通C＋＋》附盘的原代码。书上的每个例子在这里都有相应的C语言程序。

// Listing 5.8 - demonstrates
// function polymorphism

#include <iostream>

int Double(int);
long Double(long);
float Double(float);
double Double(double);

using namespace std;

int main()
{
	int      myInt = 6500;
	long     myLong = 65000;
	float    myFloat = 6.5F;
	double   myDouble = 6.5e20;

	int      doubledInt;
	long     doubledLong;
	float    doubledFloat;
	double   doubledDouble;

	cout << "myInt: " << myInt << "\n";
	cout << "myLong: " << myLong << "\n";
	cout << "myFloat: " << myFloat << "\n";
	cout << "myDouble: " << myDouble << "\n";

	doubledInt = Double(myInt);
	doubledLong = Double(myLong);
	doubledFloat = Double(myFloat);
	doubledDouble = Double(myDouble);

	cout << "doubledInt: " << doubledInt << "\n";
	cout << "doubledLong: " << doubledLong << "\n";
	cout << "doubledFloat: " << doubledFloat << "\n";
	cout << "doubledDouble: " << doubledDouble << "\n";

	return 0;
}

int Double(int original)
{
	cout << "In Double(int)\n";
	return 2 * original;
}

long Double(long original)
{
	cout << "In Double(long)\n";
	return 2 * original;
}

float Double(float original)
{
	cout << "In Double(float)\n";
	return 2 * original;
}

double Double(double original)
{
	cout << "In Double(double)\n";
	return 2 * original;
}