#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
using namespace std;
int main()
{
	ifstream filein;
	filein.open("a.txt");
	if (!filein)
	{
		cout << "Nieudana proba otwarcia pliku!" << endl;
		system("pause");
		return 1;
	}
	double d,temp[100] = { 0 };
	int ilosc = 0;
	while (ilosc < 100)
	{
		filein >> d;
		if (filein.eof())break;
		temp[ilosc] = d;
		cout << d << endl;
		ilosc++;
	}
	filein.close();
	ofstream fileout("a.txt");
	if (!fileout)
	{
		cout << "Nieudana proba otwarcia pliku!" << endl;
		system("pause");
		return 1;
	}
	for (int i = 0;i < ilosc;i++)
	{
		fileout << fixed<<setprecision(1)<<temp[i] << endl;
	}
	fileout.close();
	fileout.open("b.txt",ios::app);
	double suma = 0;
	for (int i = 0;i < ilosc;i++) suma += temp[i];
	double srednia = suma / ilosc;
	fileout << "srednia: " << fixed << setprecision(3) << srednia << endl;
	fileout.close();
	system("pause");
	return 1;
}