Data from file not saving right to an array. Why?! aaahhhh!

[angrybeaver76]

Ok I think I'm headed in the right direction, but still can't get this to work. I just can't get the right data to save into the arrays for some reason. I was able to calculate the correct letter grade and output to new file, but I want to then read all 3 rows into arrays so I can then be able to run menu options 2, 3 and 5. But the data it outputs is not right. :( why why why?

Sample "TestScores_Grades.txt" to read from:
10214 8 A-
19285 3 F
11753 5 B
11261 3 F
13893 -1 F
17611 7 A-
10587 3 F
15568 10 A

#include <cstdlib>
#include <iostream>
#include <iomanip>
#include <fstream>
#include <cmath>
#include <string>

using namespace std;

int main()
{ 
    const char FILENAME[30] = "TestScores.txt";
      
    ifstream inFile;    
    int id, score, avg, s = 0, numofstudents = 0, totalgrade = 0;
    inFile.open(FILENAME);
    
    while (!inFile.eof())
    {
          inFile >> id;
          inFile >> score;
          if (score >= 0 && score <= 10)
          {
               totalgrade = totalgrade + score;
               numofstudents++;
               s = s + 1;
          }     
    }
    avg = totalgrade/numofstudents;  
    inFile.close();
    
    
    ifstream inFile2;
    ofstream outFile1;
    int idx;
    string grade;
    
    inFile2.open(FILENAME);
    outFile1.open("TestScores_Grades.txt");
    
    for(idx = 0; idx < s; idx++)
    {
         inFile2 >> id >> score;
         if (score == avg || score == avg +1)
              grade = "B";
         else if (score == avg + 2 || score == avg + 3)
              grade = "A-";
         else if (score == avg +4 || score == 10 )
              grade = "A";
         else if (score == avg - 1)
              grade = "C";
         else if (score <= (avg - 2))
              grade = "F";
         outFile1 << id << " " << score << " " << grade << endl;
    }
    inFile2.close();
    
    
    ifstream inFile3;
    int num, ids[idx], scores[idx];
    char grades[idx];
    
    inFile3.open("TestScores_Grades.txt");
    idx = 0;
    
    while (idx <= s && !inFile3.eof())
    {
         inFile3 >> ids[idx] >> scores[idx] >> grades[idx];
         idx++;
    }
    inFile3.close();
     
    do
    {
         cout << setw(30) << "QUIZ RESULTS MENU     " << endl;
         cout << setw(30) << "***************************" << endl << endl;
         cout << "   1. " << left << setw(30) << "List by Student ID" << endl;
         cout << "   2. " << setw(30) << "List by Student ID and Grades" << endl;
         cout << "   3. " << setw(30) << "List by Letter Grade" << endl;
         cout << "   4. " << setw(30) << "List by Numeric Grade" << endl;
         cout << "   5. " << setw(30) << "List Grades by Percentage" << endl << endl;
    
         cout << right << "Enter an option: " ;
         cin >> num;
         cout << endl;
         
         if (num == 1)
              cout << "This option sorts the student list by ID and writes it to a file.";
         if (num == 2)
         {
              //Read the new file and search for the target ID that the user enters.
              ifstream inFile4;
              inFile4.open("TestScores_Grades.txt");
              int target;
                           
              for(idx = 0; idx < s; idx++)
              {
                   cout << "Enter a student ID: ";
                   cin >> target;
                   if(ids[idx] = target)
                   {
                        cout << "Result: " << ids[idx] << " " << scores[idx] << " " << grades[idx] << endl; 
                   }
              }
         }
         
         else if (num == 3)
              //cout << "This option searches for students with a particular letter grade." << endl << endl;
         {
              //Read the file again and search for the target letter grade that the user enters.
              ifstream inFile4;
              inFile4.open("TestScores_Grades.txt");
              char targetGrade;
                           
              for(idx = 0; idx < s; idx++)
              {
                   cout << "Enter a letter grade: ";
                   cin >> targetGrade;
                   if(grades[idx] = targetGrade)
                        cout << "Result: " << ids[idx] << " " << scores[idx] << " " << grades[idx]; 
              }
         }
         
         else if (num == 4)
              cout << "This option sorts the list by numeric grade.";
         else if (num == 5)
              cout << "This option calculates the % of students with a particular grade.";    
         else if (num < 1 || num > 5)
              cout << "This is an invalid entry. Please rerun the program.";
         cout << endl << endl << endl;
    }
    while (num > 0 && num <= 5);

  
    system("PAUSE");
    return EXIT_SUCCESS;
}

[Felicia123]

your coding very blur. please arrange to code using the code button

and i roughly see for few lines.
i saw that for your first inFile
you does not save it into array
while(!inFile.eof() )

try change and post problem here again

[angrybeaver76]

Oops. sorry about that Felicia. Not sure how I didn't notice that when I submitted. I just edited. How is it now?

[SamuelAdams]

The first problem I see is;

Sample "TestScores_Grades.txt" to read from:

not the name of the file in the program.

You need

   if(inFile.fail())
   {
   cout<<"Could not open Input File\n";// <<
   exit(1);//;
   }

not going to work the way it is.

one of your score's is -1, you are using int to record score

You are saying
if (score >= 0 && score <= 10)

but you have no else, so if the score is not 0-10 what happens then ?

I don't know how you would have a -1 score anyway, so that may be a typo.

[angrybeaver76]

Thanks for responding SamuelAdams!

The first file "TestScores.txt" is the original file with just 2 columns (ID's and raw number scores). The 2nd file "TestScores_Grades.txt" is created when I calculate the letter grades into the 3rd column and then I read from that file the rest of the time.

Th -1 is supposed to mean the student didn't take the test. Yea I have to reconcile those scores. Forgot those were in there, but they shouldn't be calculated into the average and I think I have that covered. Let me work on that.

Thanks for the inFile.fail!