#include <cstdlib>
#include <fstream>
#include <iostream>
#include <string>
#include <vector>
using namespace std;

int main()
{
  fstream file;
  int line_count = 0;
  int months;
  string name_file;

  std::cout << "Please input the file name for your report file: ";
  std::cin >> name_file;

  if (name_file != "load_report.txt")
  {
    std::cout << "Invalid report file!\n";
    exit(1);
  }

  std::cout << "Please provide the number of months to consolidate: ";
  std::cin >> months;

  if (months <= 0)
  {
    std::cout << "You need to have at least one month in order to"
              << " consolidate your sales.\n";
    exit(1);
  }

  std::cout << "\n";

  file.open(name_file, ios::in);

  if (file.is_open())
  {
    string line;
    while (getline(file, line))
    {
      line_count++;
    }
  }

  else
  {
    std::cout << "Could not open file!\n";
    exit(1);
  }

  file.close();

  file.open(name_file, ios::in);

  vector<float> a(line_count);

  int k = 0;

  if (file.is_open())
  {
    for (auto & val : a)
    {
      file >> val;
    }
  }

  else
  {
    std::cout << "Could not open file!\n";
    exit(1);
  }

  file.close();

  int loops = line_count / months;

  for (int i = 0; i < loops; ++i)
  {
    float sum = 0;
    std::cout << "Month ";
    for (int j = 0; j < months; ++j)
    {
      std::cout << i * months + j + 1 << " ";
      sum += a[i * months + j];
    }
    std::cout << "sales: $" << sum << "\n";
  }

  return 0;
}