#include <fstream>
#include <iostream>
#include <string>

#define length 4

using namespace std;

class NotANumber { };
int i = 0;
class Arr
{
private:
	int arr[length];
	int *temp = arr;
public:
	Arr() : arr()
	{}
	Arr(int *a)
	{
		for (int i = 0; i < length; i++)
		{
			arr[i] = a[i];
		}
	}
	int getElement(int i)
	{
		return arr[i];
	}
	int* set()
	{
		for (int i = 0; i < length; i++)
			cin >> arr[i];
		return arr;
	}
	int FindEl(int a)
	{
		for (int i = 0; i < length; i++) {
			cout << arr[i] << endl;
			if (arr[i] == a)
			{
				return i;
			}
		}
		cout << "No such element";
	}

	void PrintArray()
	{
		for (int j = 0; j < length; j++)
			cout << "arr[" << j << "]=" << arr[j] << endl;
	}

	friend ostream& operator << (ostream& os, Arr& a)
	{
		for (int i = 0; i < length; i++)
			os << a.arr[i] << " ";
		os << endl;
		return os;
	}
	friend istream& operator >> (istream& is, Arr& a)
	{
		for(int i=0;i < length;i++)
			is >>a.arr[i] ;
		return is;
	}
};

int main()
{
	char ch;
	Arr a;
	ofstream ofile;
	ofile.open("array.dat");

		cout << "Enter array" << endl;
		try
		{
			cin >> a;
			ofile << a;
		}
		catch (NotANumber)
		{
			cin.clear();
			cin.sync();
			cout << "Something wrong";
		}
		ofile.close();

		ifstream ifile;
		ifile.open("array.dat");
		cout << "\nData in file:\n";

			try
			{
				ifile >> a;
			}
			catch (NotANumber)
			{
				cout << "Something wrong";
			}
			cout << a << endl;
		ifile.close();
		getchar();
}