#include<iostream>
#include<fstream>

using namespace std;

int main ()
{
fstream Marin;

Marin.open("A.txt",ios::out);

if(Marin.fail()){cerr<<" Error Open File A.txt "<<endl;	
exit(1);
}
else	
{cout<<" OK - Open File write A.txt "<<endl;}

int V[100],n;

cout<<" Enter n element = "; cin>>n;

for(int i=0; i<n; i++)	
{
cout<<" Enter element "; cin>>V[i];
Marin<<V[i];
if(i%4==2){Marin<<endl;}		
}

Marin.close();


Marin.open("A.txt",ios::in);

if(Marin.fail())
{
cerr<<" Error Open File A.txt "<<endl;
exit(1);
}
else  
{
cout<<" OK - Open File read A.txt "<<endl;		
}

int a[100],b, i=0,R=0;

while(!Marin.eof())
{	
Marin>>a[i];
R+=a[i];	
i++;	
;}

Marin.close();
cout<<" Rez = "<<R;

	return 0;
}