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array problem

geharbison (40)
I cannot understand why my program only spits out garbage. Here are the letters if you wish to plug them in with a .txt file:
correctanswers.txt

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studentanswers.txt
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C

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  #include <iostream>
#include <fstream>

using namespace std;

void getRscore(char[], int);
void getBscore(char[], int);
char compare(char[], char[], int);

const int SIZE=20;

int main ()
{
    int amountwrong;
    char studentanswers[SIZE];
    char correctanswers[SIZE];
    char wrong[SIZE];
    int countdex=0;
    
    
    getRscore(studentanswers, SIZE);
    
    getBscore(correctanswers, SIZE);
    
    


     
     
     
     for (int index = 0; index<SIZE; index++)
         {
         while (studentanswers[index]!=correctanswers[index])

              {
              wrong[countdex]=studentanswers[index];
              
              countdex++;}}



              
     
              cout<<"The student answers have been pulled from their file and compared to \n";
              cout<<"the correct answers. The amount of answers that were wrong is: " <<countdex <<endl;
              cout<<"The incorrect answers are as follows: ";
              for (int count=0; count<countdex; count++)
          cout<<wrong[count];             
              
 
              
                                            
    
 
 
 
 
 
 
 
 
 
 
 
 
 
     system ("pause");
    return 0;
}

void getRscore(char score[], int SIZE)

{
     ifstream Answers;
     
     Answers.open("StudentAnswers.txt");
    char answers[20];
    int count=0;
    while (count<20 && Answers)
     Answers>>score[count];
     count++;
     
     Answers.close();
 for(int index=0; index<20; index++)
  cout<<answers[index] <<" ";
}



void getBscore(char Score[], int SIZE)

{
     ifstream answers;
     
     answers.open("CorrectAnswers.txt");
     
     int count=0;
     while (count<SIZE && answers >> Score[count])
     count++;
     
     answers.close();
     
}






















            
+
Yanson (885)
You still haven't made the changes I mentioned the first time you posted.
http://cplusplus.com/forum/beginner/99538/

You are not checking that the file opens properly
you still have a function prototype for a compare function you are not using
You don't need an answers array.
The loop on line 84-85 is not needed and will output garbage because you never put anything into the array.
Your loop on line 79 is wrong if you are going to use a counting loop consider using a for loop
and whats with the + on line 127? this is a syntax error that should have been fixed before posting
Last edited on
geharbison (40)
I have solved my problem opening the file, and I think I have most everything corrected that you said to. When I run it now, it says that 50 questions were answered incorrectly. There are only supposed to be 20 answers. I think the problem is in the comparison of the two arrays. 



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#include <iostream>
#include <fstream>

using namespace std;

void getRscore(char[], int);
void getBscore(char[], int);


const int SIZE=20;

int main ()
{
    int amountwrong;
    char studentanswers[SIZE];
    char correctanswers[SIZE];
    char wrong[SIZE];
    int countdex=0;
    
    
    getRscore(studentanswers, SIZE);
    
    getBscore(correctanswers, SIZE);
    
    


     
     
     
     for (int index = 0; index<SIZE; index++)
         {
         while (studentanswers[index]!=correctanswers[index])

              {
              wrong[countdex]=studentanswers[index];
              
              countdex++;}}



              
     
              cout<<"The student answers have been pulled from their file and compared to \n";
              cout<<"the correct answers. The amount of answers that were wrong is: " <<countdex <<endl;
              cout<<"The incorrect answers are as follows: ";
              for (int count=0; count<countdex; count++)
          cout<<wrong[count];             
              
 
              
                                            
    
 
 
 
 
 
 
 
 
 
 
 
 
 
     system ("pause");
    return 0;
}

void getRscore(char score[], int SIZE)

{
     ifstream Answers;
     
    
     Answers.open("StudentsAnswers.txt");
    
    
    if (Answers)
   { 
    
    
    
    while (Answers)
     {for (int count=0; count<20; count++)
     Answers>>score[count];}
    
     
     Answers.close();
                           }


    else 
         {cout<<"The file 'StudentAnswers.txt.' did not open correctly."; }








}






void getBscore(char Score[], int SIZE)

{
     ifstream answers;
     
     answers.open("CorrectAnswers.txt");
     
     if (answers)
        {
     
     int count=0;
     
     while (count<SIZE && answers >> Score[count])
     count++;
     
     answers.close();}
     
     else
     {"The file 'CorrectAnswers' did not open correctly";}



     
}
Yanson (885)
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#include <iostream>
#include <fstream>
#include <cstdlib>
using namespace std;

void getRscore(char[]);
void getBscore(char[]);

const int SIZE = 20;

int main ()
{
	
	char studentanswers[SIZE];
	char correctanswers[SIZE];
	char wrong[SIZE];
	int numberWrong = 0;


	getRscore(studentanswers);

	getBscore(correctanswers);

	for (int index = 0; index < SIZE; index++)
	{
		if (studentanswers[index] != correctanswers[index])
		{
			wrong[numberWrong] = studentanswers[index];
			numberWrong++;
		}
	}
	
	cout<<"The student answers have been pulled from their file and compared to \n";
	cout<<"the correct answers. The amount of answers that were wrong is: " <<numberWrong<<endl;
	cout<<"The incorrect answers are as follows: ";
	
	for(int i = 0; i < numberWrong; i++)
	{
		cout  << wrong[i] << " ";
	}

	cout << endl;

	system ("pause");
	return 0;
}

void getRscore(char score[])

{
	ifstream inFile;
	int count = 0;

	inFile.open("StudentAnswers.txt");
	if (inFile.fail())
	{
		cerr << "File failed to open " << endl;
		cin.ignore();
		exit(0);
	}

	inFile >> score[count];
	
	while(!inFile.eof())
	{
		count++;
		inFile >> score[count];	
	}

	inFile.close();
}



void getBscore(char score[])

{
	ifstream inFile;
	int count = 0;

	inFile.open("CorrectAnswers.txt");
	
	if (inFile.fail())
	{
		cerr << "File failed to open " << endl;
		cin.ignore();
		exit(0);
	}

	inFile >> score[count];

	while(!inFile.eof())
	{
		count++;
		inFile >> score[count];
	}

	inFile.close();

}
geharbison (40)
If you have time, can you please explain what I've done wrong so that I'll know in the future what not to do?
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