C++ primer plus（3.7习题程序）

运行环境是vs2017。稍加调试可用。

3.7.1习题

//C++ primer plus  3.7.1习题
#include 
const int moon=12;
using namespace std;
int main()
{
	
	int a,b,c;
	cout << "请输入一个整数值：______bbbbbb";
	cin >> a;
	b = a / moon;
	c = a % moon;
	cout << a << "英寸 = " << b << "英尺" << c << "英寸" << endl;

	return 0;
}

 3.7.2习题

//C++ primer plus  3.7.2习题
#include 
using namespace std;
int main()
{


	//输入身高计算bmi，并换算成英制，为下一段程序提供英尺和英寸数据
	

	
	
	double a, b, c, d, e,bmi,gao;
		cout<<"输入a（英尺）和b（英寸）的值：_______bbbbbbb:";
		cin >> a >> b;
		gao = 0.0254*(a * 12 + b);
		cout << a<<"英尺"<> c;
		d = c *2.2;
		cout << c << "磅=" << d << "千克" << endl;
		bmi = d / (gao*gao);
		cout << "身高为" << a << "英尺" << b << "英寸，体重为" << c << "磅，则bmi为" << bmi << endl;

	return 0;
}

3.7.3 习题

//C++ primer plus  3.7.3习题
#include 
//const int moon=12;
const int dul = 60;
using namespace std;
int main()
{
	
	double a, b, c, d;
	cout << "Enter a latitude in degrees,minutes,and seconds:" << endl
		<< "First,enterr the degrees:";
	cin >> a;
	cout << "Next,enter the minutes of arc:";
	cin >> b;
	cout << "Finally,enter the minutes of arc:";
	cin >> c;
	d = a + b / dul + c / dul / dul;
	cout << a << " degrees, " << b << " minutes, " << c << " seconds =" << d << " degrees";
	
	return 0;
}

3.7.4 习题

//C++ primer plus  3.7.4习题
#include 
const int dul = 60;
using namespace std;
int main()
{

	int a, b, c, d, e,zan;
//	cout << INT_MAX;
	cout << "Enter the number of seconds:";
	cin >> a;
	e = a % dul;//秒
	zan = a / dul;

	d = zan % dul;//分
	zan = zan / dul;

	c = zan % dul;//时
	b = zan/24;//天

	cout << a << " seconds = " << b << " day, " << c << " hours, " << d << " minutes, "< 
 int：2147483647，也足够存储示例里的31600000。
 
3.7.5习题
 
//C++ primer plus  3.7.5习题
#include 
//const int moon=12;
using namespace std;
int main()
{
	long long a, b;
	double c;
	cout<<"Enter the world's population: ";
	cin >> a;
	cout << "Enter the population of the US:";
	cin >> b;
	c = (double)b /(double) a * 100;

	cout << "The population of the US is "< 
3.7.6 习题
 
每加仑英里数（mpg）：里程（英里）/汽油量（加仑）
 
每100公里耗油量：汽油量（升）/[距离（公里）/100]
 
//C++ primer plus  3.7.6习题
#include 
using namespace std;
int main()
{	


	double a, b, x, c, d, y;
	cout<<"输入里程（英里）和汽油量（加仑）的值：";
	cin >> a >> b;
	x = a / b;
	cout << "汽车耗油量为一加仑的里程： "<> c >> d;
	y = d / (c / 100);
	cout << "每100公里的耗油量： " <<  y<<"升"<< endl;

	return 0;
}
 
3.7.7习题
 
//C++ primer plus  3.7.7习题
#include 
using namespace std;
int main()
{	
	double a, b, x, c, d, y;
	cout<< "输入"每100公里的耗油量"： ";
	cin >> a ;
	x = 1/(a/(3.875*62.14));
	cout << "每加仑燃料"< 
美国方法=1/ [ (升/3.875)/(公里/100*62.14)]