Thread: Records(structs) pgrm help.

Write a program that reads a student's name followed by their test score. The program should output each students name followed by the test scores and the relevant grade. It should also find and print the highest test score and the name of the students having the highest test score.

Student data should be stored in a struct variable of type studentType, which has four components: studentFName and studentLName of type string, testscore of type int (testscore is between 0 and 100), and grade of type char. Suppose that the class has 20 students. Use an array of 20 components of type studentType.

The program must contain at least the following functions:

a.) a function to read the students data into the array.'
b.) a function to assign the relevant grade to each student.
c.) a function to find the highest test score.
d.) a function to print the names of the students having the highest test score.

The program must output each students name in this form: last name followed by a comma, followed by a space, followed by the 1st name, and the name must be left-justified. Moreover, other than declaring the variables and opening the input and output files, the function main should only be a collection of functions calls.

I am really stuck on this and would like some help. I have a mac and am using codeblocks. My issue is that it compiles, but it keeps stopping at finding the data file.

Code:

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


using namespace std;


const int NO_OF_STUDENTS = 20;


struct studentType
{
    string studentFName;
    string studentLName;
    int testScore;
    char grade;
};


void getData(ifstream& inData, studentType sList[], int listSize);
void calculateGrade(studentType sList[], int listSize);
int highestScore(const studentType sList[], int listSize);
void printResult(ofstream& outData, const studentType sList[], int listSize);


int main()
{
    ifstream inData;
    ofstream outData;
    studentType studentList[NO_OF_STUDENTS];
    inData.open("Data.txt");
    if (!inData)
    {
        cout << "The input file does not exist."
            << endl;
        system("PAUSE");
        return 1;
    }


    outData.open("DataOut.txt");
    if (!outData)
    {
        cout << "Could not open the output file."
            << endl;
        system("PAUSE");
        return 1;
    }


    getData(inData, studentList, NO_OF_STUDENTS);
    calculateGrade(studentList, NO_OF_STUDENTS);
    printResult(outData, studentList, NO_OF_STUDENTS);
    system("PAUSE");
    return 0;
}


void getData(ifstream& inFile, studentType sList[], int listSize)
{
    for (int i = 0; i < listSize; i++)
        inFile >> sList[i].studentFName >> sList[i].studentLName
        >> sList[i].testScore;
}


void calculateGrade(studentType sList[], int listSize)
{
    int score;
    for (int i = 0; i < listSize; i++)
        if (score >= 90)
            sList[i].grade = 'A';
        else if (score >= 80)
            sList[i].grade = 'B';
        else if (score >= 70)
            sList[i].grade = 'C';
        else if (score >= 60)
            sList[i].grade = 'D';
        else
            sList[i].grade = 'F';


}


int highestScore(const studentType sList[], int listSize)
{
    int score[100];
    int highscore = score[0];
    for (int i = 0; i < listSize; i++)
    {


        if (score[i] > highscore)
        {
            highscore = score[i];
        }


    }


}
    void printResult(ofstream& outFile, const studentType sList[], int listSize)
    {
        int maxScore = highestScore(sList, listSize);
        int i;
        outFile << setw(15) << "Student Name" << setw(10) << "Test Score" << setw(7) << "Grade" << endl;
        for (i = 1; i < listSize; i++)
        outFile << left << setw(25) << sList[i].studentLName + ", " + sList[i].studentFName<< right << " " << setw(5) << sList[i].testScore<< setw(6) << " " << sList[i].grade << endl;
        outFile << endl << "The higest test score is: " << maxScore << endl;
        outFile << "Students the have the higest test scores are:" << endl;
        for (i = 1; i < listSize; i++)
            if (sList[i].testScore == maxScore)
                outFile << sList[i].studentLName + ", " + sList[i].studentFName << endl;
    }

main.cppData.txt

You just need to create DataOut.txt file because for some reason I cannot upload/attach the empty file.

Thank you.

Yes, like so:

Code:

int main()
{
    constexpr int NO_OF_STUDENTS = 20;
}

It's usually bad practice to declare variables globally (i.e. outside of main).

As for constexpr, it's like const but for values known at compile time:

Code:

void fn(int value)
{
    constexpr int testRuns = 15; // testRuns is always 15, it's hard-coded

    const int valueTwice = value * 2; // valueTwice won't change after being declared, but value might be computed at runtime
}

Oh ok that makes sense.
As for the highest score, I am not understanding the idea of what you are saying.
I downloaded the Xcode 7 beta and its giving me trouble, so going to try Xcode 6.4
The current error I am receiving is just warnings on codeblocks. I put the textiles in the main.cpp directory, but its still not doing anything.

Here is the warning I am getting
++ -Wall -fexceptions -g -c /Users/yashpatel/Documents/YPatelLab1/main.cpp -o obj/Debug/main.o
/Users/yashpatel/Documents/YPatelLab1/main.cpp:64:7: warning: variable 'score' is uninitialized when used here [-Wuninitialized]
if (score >= 90)
^~~~~
/Users/yashpatel/Documents/YPatelLab1/main.cpp:62:11: note: initialize the variable 'score' to silence this warning
int score;
^
= 0
/Users/yashpatel/Documents/YPatelLab1/main.cpp:91:1: warning: control reaches end of non-void function [-Wreturn-type]
}
^
2 warnings generated.
g++ -o bin/Debug/YPatelLab1 obj/Debug/main.o
Output file is bin/Debug/YPatelLab1 with size 63.52 KB
Process terminated with status 0 (0 minute(s), 2 second(s))
0 error(s), 2 warning(s) (0 minute(s), 2 second(s))

Yes but what if more than one person has the same score? If lets say 3-4 students have 100%. So do I remove that integer?

Oh right, I hadn't even looked at the printResult function. To allow for multiple high scorers, some sort of array is needed of course; disregard my advice in that case. Assuming you haven't learned about containers like std::vector yet, you will have to create an array (or two) outside of your highestScore function and then pass these as arguments (to be modified).

Ok so Xcode is working better than code blocks.
Here is what I am getting.

Data.txt:
Clark Kent 100
Bruce Wayne 100
Barry Allen 100
Diana Prince 90
Kara Kent 92
Hal Jordan 98
Billy Batson 96
Arthur Curry 38
John Jones 24
Oliver Queen 52
Carter Hall 22
Shiera Hall 72
Zatanna Zatara 82
Ray Palmer 62
Michael Carter 68
Kent Nelson 46
Nathaniel Adam 88
Karen Starr 78
Terry Mcginnis 42
Dick Grayson 56

Student NameTest Score Grade
Wayne, Bruce 100 A
Allen, Barry 100 A
Prince, Diana 90 A
Kent, Kara 92 A
Jordan, Hal 98 A
Batson, Billy 96 A
Curry, Arthur 38 A
Jones, John 24 A
Queen, Oliver 52 A
Hall, Carter 22 A
Hall, Shiera 72 A
Zatara, Zatanna 82 A
Palmer, Ray 62 A
Carter, Michael 68 A
Nelson, Kent 46 A
Adam, Nathaniel 88 A
Starr, Karen 78 A
Mcginnis, Terry 42 A
Grayson, Dick 56 A


The higest test score is: 0
Students the have the higest test scores are:

I am really stuck, if you could show me that would be really helpful. I know I am almost there, but still getting errors. Clark Kent disappears from the list, its not giving the highest score and names, also everyone is getting an A.

I wanted to guide you to the solution, but I guess it's time to show it directly:

Code:

void calculateGrades(studentType sList[], int listSize)
{
    int score;
    for (int i = 0; i < listSize; i++)
        score = sList[i].testScore; // <- you were missing this. 'score' never acquired a value to compare with others
        if (score >= 90)
            sList[i].grade = 'A';
        else if (score >= 80)
            sList[i].grade = 'B';
        else if (score >= 70)
            sList[i].grade = 'C';
        else if (score >= 60)
            sList[i].grade = 'D';
        else
            sList[i].grade = 'F';
}

Note that I've made the function name plural. It calculates grades and the name should reflect that.

Regarding your highestScore function (should be Scores too, as you work with more than one), what is your rationale behind it? In other words, how would you describe in written words what it does to arrive at a result? This is probably something your tutor wants you to work out. The coding part I can help you with, but the logic part is on you, or I'd be doing your homework

In your current approach, one immediate problem is that you have an uninitialised array score[100] that you're trying to do work with. What do you think the value of score[0] on line 4 is?

Code:

int highestScore(const studentType sList[], int listSize)
{
    int score[100];
    int highscore = score[0];
    for (int i = 0; i < listSize; i++)
    {
        if (score[i] > highscore)
        {
            highscore = score[i];
        }
}