1. ## Looping decision?

Hello,

I am trying to figure out how or what looping method
to use to read multiple data from a file.
The file has several income brackets (A, B, & C), and some ratings for product1 and product2.
The data file looks like this:
Code:
```A 5 7
A 4 8
A 3 9
B 2 7
C 1 6
C 8 2
A 7 5
B 6 9```
What I want to do is read in and calculate the average rating for product 1 (the first number)
that bracket A rated, then bracket B,
and finally C.
I have figured out how to read A or B or C,
by using an if statement and simply changing
the argument to A or B or C,
but I don't know how to have it read the data for A,
then read B, and then C without intervening.
Here is the code I have so far:

Code:
```/* This program will display for each income bracket
(A,B, & C) the average rating for
* product 1. */

#include <iostream>    // cout, cin, <<, >>
#include <string>      // string
#include <cstdlib>     // exit()
#include <cassert>     // assert
#include <fstream>     // ifstream
using namespace std;

char income,
c;
int count,
incomeB5Up,
prod2Ave;
double prod1Total;
double prod1AveA,
prod1AveB;
double prod1,
prod2;

int main()
{
string fileName;
cout << "Enter name of file: ";
getline(cin, fileName);

ifstream inFile(fileName.data());
assert(inFile.is_open() );

while (inFile.get (c) )
{

if (c == 'A')  /* get income bracket A information */
{
count++;
inFile >> prod1 >> prod2;
cout << "Product 1 rating: " << prod1 << " Product 2 rating: "
<<  prod2 << " Count: " << count << "\n";  // display prod ratings read from file
prod1Total += prod1;
cout << "Prod1Total = " << prod1Total << "\n";    // display prod1 total
prod1AveA = prod1Total / count;
cout << "Average for Product 1 in income class A: " << prod1Ave << "\n\n";
}

}
cout << "Average for Product 1 in income class A: " << prod1AveA << "\n\n";

}```

2. the structure of the file is illusion

read the file as a continuous stream of single characters

encounter A, B, or C - set an index in a two dimensional array of averages

next character should be a digit - set an indexto the product in your two dimensional array

next character is your score - combine it into the average: (average[incomebracket][productnumber] + rating) / 2

hope this helps

3. I don't know how to use arrays yet.

4. here is forbidden knowledge

float array[3][3];

now you can access array[x][y], where 0 <= x <= 2 and 0 <= y <= 2 and use it as a spreadsheet-like block of floats