#include <fstream>
#include <iostream>
#include <iomanip>
#include <cstdlib>
 
using namespace std;
 
const int MAXLEN_FN = 30;
 
void OptionPrompt();
void Process(int *scoresArrayPtr, int numOfScores,
             int& highestScore, int& lowestScore,
             double& averageScore);
void CoutResults(int *scoresArrayPtr, int numOfScores,
                 int highestScore, int lowestScore,
                 double averageScore);
 
int main()
{
   int *scoresArrayPtrHold = 0, *scoresArrayPtr = 0;
   int arraySize = 0, numOfScores = 0, score,
       lowestScore, highestScore;
   double averageScore;
   char inputFilename[MAXLEN_FN + 1],
        reply;
   ifstream fin;
   ofstream fout;
 
   cout << "I can process almost any # of scores for you" << endl;
   OptionPrompt();
 
   do
   {
      cin >> reply;
      cin.ignore(999, '\n');
      if (reply != '1' && reply != '2')
      {
         cout << "You have entered an invalid option" << endl;
         cout << "Please re-enter your desired option" << endl;
         OptionPrompt();
      }
   } while (reply != '1' && reply != '2');
 
   if (reply == '1')
   {
      cout << "Enter the 1st score (any invalid score to quit): ";
      cin >> score;
      while (score >= 0 && score <= 100)
      {
         ++numOfScores;
         if (numOfScores > arraySize)
         {
            arraySize = int(1.5*arraySize + 1);
            scoresArrayPtrHold = scoresArrayPtr;
            scoresArrayPtr = new int [arraySize];
            for (int i = 0; i < numOfScores - 1; ++i)
               *(scoresArrayPtr + i) = *(scoresArrayPtrHold + i);
            delete [] scoresArrayPtrHold;
            scoresArrayPtrHold = 0;
         }
         *(scoresArrayPtr + numOfScores - 1) = score;
 
         cout << "Enter the next score (any invalid score to end): ";
         cin >> score;
      }
 
      if (numOfScores > 0)
      {
         Process(scoresArrayPtr, numOfScores, highestScore,
                 lowestScore, averageScore);
         CoutResults(scoresArrayPtr, numOfScores, highestScore,
                     lowestScore, averageScore);
      }
      else
         cout << "No scores to process..." << endl;
   }
   else
   {
      cout << "Enter name of input file (up to "
           << MAXLEN_FN << " characters): ";
 
      int count = 0;
      char oneChar;
 
      oneChar = cin.get();
      while (oneChar != '\n')
      {
         if (count < MAXLEN_FN)
         {
            inputFilename[count] = oneChar;
            ++count;
         }
         oneChar = cin.get();
      }
      inputFilename[count] = '\0';
 
      fin.open(inputFilename, ios::in);
      if (fin.fail())
      {
         cout << "Error opening file " << inputFilename << endl;
         exit(EXIT_FAILURE);
      }
 
      fout.open("ASSIGN08.OUT", ios::out);
      if (fout.fail())
      {
         cout << "Error opening file ASSIGN08.OUT" << endl;
         fin.close();
         exit(EXIT_FAILURE);
      }
 
      fin >> score;
      while ( ! fin.eof() )
      {
         ++numOfScores;
         fin >> score;
      }
 
      if (numOfScores > 0)
      {
         fin.clear();
         fin.seekg(0);
         scoresArrayPtr = new int [numOfScores];
         for (int i = 0; i < numOfScores; ++i)
            fin >> *(scoresArrayPtr + i);
         Process(scoresArrayPtr, numOfScores, highestScore,
                 lowestScore, averageScore);
         CoutResults(scoresArrayPtr, numOfScores, highestScore,
                     lowestScore, averageScore);
 
         fout << "Scores read: ";
         for (int j = 0; j < numOfScores; ++j)
            fout << *(scoresArrayPtr + j) << ' ';
         fout << endl;
         fout << "# of valid scores: " << numOfScores << endl;
         fout << "Highest score: " << highestScore << endl;
         fout << "Lowest score : " << lowestScore << endl;
         fout << "Average score: "
              << setiosflags(ios::fixed | ios::showpoint)
              << setprecision(2) << averageScore << endl;
      }
      else
      {
         cout << "No scores to process..." << endl;
         fout << "No scores to process..." << endl;
      }
      fin.close();
      fout.close();
        }
 
   delete [] scoresArrayPtr;
   scoresArrayPtr = 0;
 
   return EXIT_SUCCESS;
}
 
void OptionPrompt()
{
   cout << "You have the following options:" << endl;
   cout << "1  Enter the scores interactively" << endl
        << "   (results are output to screen only)" << endl;
   cout << "2  Specify a file containing the scores" << endl
        << "   (results are output to screen and file)" << endl
        << "   (name of output file will be ASSIGN08.OUT)"
        << endl;
   cout << "Your choice? ";
}
 
void Process(int *scoresArrayPtr, int numOfScores,
             int& highestScore, int& lowestScore,
             double& averageScore)
{
   int sum = lowestScore = highestScore = *scoresArrayPtr;
   for (int k = 1; k < numOfScores; ++k)
   {
      sum += *(scoresArrayPtr + k);
      if (*(scoresArrayPtr + k) < lowestScore)
         lowestScore = *(scoresArrayPtr + k);
      else if (*(scoresArrayPtr + k) > highestScore)
         highestScore = *(scoresArrayPtr + k);
   }
   averageScore = double(sum) / numOfScores;
}
 
void CoutResults(int *scoresArrayPtr, int numOfScores,
                 int highestScore, int lowestScore,
                 double averageScore)
{
   cout << "Scores read: ";
   for (int j = 0; j < numOfScores; ++j)
      cout << *(scoresArrayPtr + j) << ' ';
   cout << endl;
   cout << "# of valid scores: " << numOfScores << endl;
   cout << "Highest score: " << highestScore << endl;
   cout << "Lowest score : " << lowestScore << endl;
   cout << "Average score: "
        << setiosflags(ios::fixed | ios::showpoint)
        << setprecision(2) << averageScore << endl;
}