How to add a Average of the numbers in c++ text.stream

Question

How to code Average of the numbers in case 5? I already done a convert string to int. How can I make average of the numbers from text file named "dane.txt"?

case 5: //srednia
                {
                    fstream plik;
                    plik.open("dane.txt");
                    while(!plik.eof())
                    {
                        plik>>a;
                        licznik++;
                        if((licznik)%3 == 0)
                        {
                            string str = a;
                            int m = atoi(str.c_str());
                            
                        }
                    }
                    plik.close();
                    break;
                }

question from:https://stackoverflow.com/questions/65914999/how-to-add-a-average-of-the-numbers-in-c-text-stream

Answer 1

Add two variables to keep track of the count of numbers, and the total from adding up all the numbers (apologies for the English names).

Then at the end of the loop you can divide the total by the count and that is your average.

                int total = 0;
                int count = 0;
                ...
                while(...)
                {
                        ...
                        string str = a;
                        total += atoi(str.c_str());
                        ++count;
                }
                cout << "average is " << (double)total/count << '
';