【第三章】C++ Primer plus 的编程练习题(选取部分)

/***********************************
2017年9月26日16:56:31
Athor：xiyuan255
Course：C++
Contain：myfirst.cpp
Reference: C++ Primer plus
说明：C++ Primer plus第三章的练习题(选取部分)
【 P69 】
*************************************/
// review3.cpp -- C++ Primer plus 第三章练习题

#include <iostream>

using namespace std;

void exampleNo2(void);
void exampleNo3(void);
void exampleNo4(void);
void exampleNo7(void);

int main(void)
{
//exampleNo2(); // example 2 test
//exampleNo3(); // example 3 test
//exampleNo4(); // example 4 test
exampleNo7(); // example 7 test

return 0;
}

void exampleNo7(void)
{
cout << "请按欧洲风格输入汽车的耗油率(升/100km)：";
double mile_kilome;
cin >> mile_kilome;
const double Litre = 3.875;
const double Mile = 62.14;
double gallon = mile_kilome / Litre;
int mpg = int(Mile / gallon);
cout << "转化成美国风格的耗油量(每加仑多少英里)："
<< mpg << "mpg.\n";
}
/**
输出结果：
请按欧洲风格输入汽车的耗油率(升/100km)：12.41
转化成美国风格的耗油量(每加仑多少英里)：19mpg.
*/

void exampleNo4(void)
{
cout << "Enter the number of seconds: ";
long long seconds;
cin >> seconds;
const short Hour = 24;
const short Minute = 60;
const short Second = 60;
int days = seconds / (Hour * Minute * Second);
int hours = seconds % (Hour * Minute * Second) / (Minute * Second);
int mintes = (seconds % (Hour * Minute * Second)) % (Minute * Second) / Second;
int second = seconds % Second;

cout << seconds << " seconds = " << days << " days, " << hours << " hours, "
<< mintes << " mintues, " << second << " seconds.\n";

}
/**
输出结果：
Enter the number of seconds: 31600000
31600000 seconds = 365 days, 17 hours, 46 mintues, 40 seconds.
*/

void exampleNo3(void)
{
cout << "Enter a latitude in degrees, minutes and seconds: \n";
cout << "First, enter the degrees: ";
int degrees;
cin >> degrees;
cout << "Next, enter the minutes of arc: ";
int minutes;
cin >> minutes;
cout << "Finally, enter the seconds of arc: ";
int seconds;
cin >> seconds;

const int Minute = 60;
const int Second = 60;
double degre = double(degrees) + double((double)minutes/Minute)
+ double((double)seconds/(Second * Minute));
cout << degrees << " degrees, " << minutes << " mintes, "
<< seconds << " seconds = " << degre << " degrees.\n";
}
/**
输出结果：
Enter a latitude in degrees, minutes and seconds:
First, enter the degrees: 37
Next, enter the minutes of arc: 51
Finally, enter the seconds of arc: 19
37 degrees, 51 mintes, 19 seconds = 37.8553 degrees.
*/

void exampleNo2(void)
{
cout << "以几英尺几英寸的方式输入身高,"
<< "并以磅为单位输入其体重：\n";
cout << "英尺：";
int feets = 0;
cin >> feets;
cout << "英寸：";
int inchs = 0;
cin >> inchs;
cout << "体重：";
int pounds;
cin >> pounds;

const short British = 12;
const float Metric = 0.0254f;
const float Pound = 2.2f;
double meter = double (Metric * (feets * British + inchs));
double kilogram = double (pounds / Pound);
double BMI = double (pow(kilogram/meter, 2));
cout << "meter = " << meter << ", kilogram = " << kilogram << endl;
cout << "BMI = " << BMI << " Done!\n";

}
/**
输出结果：
以几英尺几英寸的方式输入身高,并以磅为单位输入其体重：
英尺：5
英寸：10
体重：130
meter = 1.778, kilogram = 59.0909
BMI = 1104.53 Done!
*/