Write a program that reads a file of numbers and output all the numbers and the average of the numbers into another file

[answerhappygod]

Write a program that reads a file of numbers and output all
the numbers and the average of the numbers into another file. The
input file name is txt1In.txt and it contains 6 numbers of type
double separated by blanks or line breaks. Name the output file
txt2Out/txt.
I seem to have confused myself in outputting the average I was
able to output the list of numbers just confused where to put the
average please help?
int main()
{//declaration
double n;
double number;
ifstream in_Stream;
ofstream out_Stream;
in_Stream.open("twelveTwoIn.txt");//opening
input file
if(in_Stream.fail( ))//if input file doesn't
exist
{
cout << "Error opening
input file"<<endl;
exit (1);
}
out_Stream.open("twelveTwoOut.txt");//creating output
file
if(out_Stream.fail( ))
{
cout << "Error opening
output file"<<endl;//if an error creating
exit(1);
}
//processing 6 numbers writing them to output
file
for (int i = 0; i < 6; i++)
{
in_Stream >> number;
out_Stream << number <<
endl;
}
//calculating the average
double sum=0;
int count=0;
while(!in_Stream.eof())
{
in_Stream >> n;
sum += n;
count++;
}
double avg=0;
avg = sum/double (count);
//Writing to output file
out_Stream << "The average: " << avg
<< endl;
//output to screen
cout << "The average is: " << avg
<< endl; //output to screen as a checker
in_Stream.close();
out_Stream.close();
return 0;
}