#include <iostream>
#include <fstream>//包含头文件
int main()
{
	using namespace std;
	char automobile[50];
	int year;
	double a_price;
	double d_price;
	ofstream outFile;//1.创建ofstream
	outFile.open("carinfo.txt");//2.将该ofstream与一个文件关联起来
	cout<<"Enter the make and model of automobile";
	cin.getline(automobile,50);
	cout<<"Enter the model year:";
	cin>>year;
	cout<<"Enter the original asking price: ";
	cin>>a_price;
	d_price = 0.913*a_price;
	cout<<fixed;
	cout.precision(2);
	cout.setf(ios_base::showpoint);
	cout<<"Make and model : "<<automobile<<endl	;
	cout<<"Year: "<<year<<endl;
	cout<<"Was asking $ "<<a_price<<endl;
	cout<<"Now asking $ "<<d_price<<endl;
 
	//3.同cout一样使用
	outFile<<fixed;
	outFile.precision(2);
	outFile.setf(ios_base::showpoint);
	outFile<<"Make and model : "<<automobile<<endl	;
	outFile<<"Year: "<<year<<endl;
	outFile<<"Was asking $ "<<a_price<<endl;
	outFile<<"Now asking $ "<<d_price<<endl;
	outFile.close();//4.使用完关闭文件流
	system("pause");
}

/************************************************************************/
/* 
	 文件的输入流                         
	 1.包含头文件
	 2.定义一个用处理输入的ifstream
	 3.将文件与ifstream对象关联起来
	 4.结合使用ifstream eof,fail 等方法来判断输入是否成功
	 5.关闭ifstream
*/
/************************************************************************/
#include <iostream>
#include <fstream>
#include <cstdlib>
#define SIZE 60
int main()
{
	using namespace std;
	char filename[SIZE];
	ifstream inFile;
	cout<<"Enter name of data file: ";
	cin.getline(filename,SIZE);
	inFile.open(filename);
	if (!inFile.is_open())
	{
		cout<<"Could not open the file "<<filename<<endl;
		cout<<"Program terminating.\n";
		exit(EXIT_FAILURE);
	}
	double value;
	double sum = 0.0;
	int count =0;
	inFile>>value;
	while (inFile.good()){
		++count;
		sum +=value;
		inFile>>value;
	}
	if (inFile.eof()){
		cout<<"End of file reached.\n";
	}else if (inFile.fail()){
		cout<<"Input terminated by data mismatch.\n";
	}else{
		cout<<"Input terminated for unkonw reason.\n";
	}
	if (count == 0){
		cout<<"No data processed.\n";
	}else{
		cout<<"Item read: "<<count<<endl;
		cout<<"Sum: "<<sum<<endl;
		cout<<"Average: "<<sum/count<<endl;
	}
	inFile.close();
	system("pause");
	return 0;
}