How to sort array contants in a structures in alphabetical orders C++

[ana_1234]

I have an assignment in class I'm and almost done but I need help with one part.

Within each subject in the output file, list the students in alphabetic order, sorted by last name. Do not change the given case (upper/lower case) of the names that were read from the input file when you print the output file. However, this sort needs to be true alphabetical (not just the "lexicographical" sort).

#include <iostream>
#include <iomanip>
#include <fstream>
#include <cctype>
#include <cstdlib>
#include <cstring>
using namespace std;

struct Student
{
    char lastname[20];
    char firstname[20];
    char course;
    int grade1;
    int grade2;
    int final;
    double average;
};

void openFile (ofstream &, ifstream &, char[]);
void PrintClass (Student*, ofstream &, int, char);
double TestAverage (const Student&);
char Grade (const Student&);
void Alphasort (Student*, int);

int main()
{
    Student* students = NULL; 
    char filename[25];  // a string for filenames
    ifstream in1;       // a file input stream
    ofstream out1;       // a file output stream
    int classSize;

    openFile (out1, in1, filename);



    in1 >> classSize;

    students = new Student[classSize];

    for( int i = 0; i < classSize; i++)
    {
        in1.ignore(80, '\n');
        in1.getline(students[i].lastname, 20, ',');
        in1.getline(students[i].firstname, 20, ',');
        in1.get(students[i].course);
        in1.ignore(80, ',');
        in1 >> students[i].grade1;
        in1.ignore(80, ',');
        in1 >> students[i].grade2;
        in1.ignore(80, ',');
        in1 >> students[i].final;
        students[i].average = TestAverage (students[i]);
    }


    out1 << "Student Grade Summary" << endl;
    out1 << "---------------------" << endl << endl;

    out1 << "ENGLISH CLASS" << endl;
    PrintClass (students, out1, classSize, 'E');


    out1 << "HISTORY CLASS" << endl;
    PrintClass (students, out1, classSize, 'H');

    out1 << "MATH CLASS" << endl;
    PrintClass (students, out1, classSize, 'M');


    delete [] students;

    return 0;

}
// this function will read the file

void openFile (ofstream& out1, ifstream& in1, char filename[])
{
    do
   {
    in1.clear();    // to clear status flags in the stream

        cout << "Please enter the name of the input file.\n";
        cout << "Filename:  ";
        cin >> filename;

        in1.open(filename);
        if (!in1)
            cout << "That is not a valid file.  Try again!\n";

   } while (!in1);

   do
   {
    out1.clear();   // to clear status flags in the stream

        cout << "Please enter the name of the output file.\n";
        cout << "Filename:  ";
        cin >> filename;

        out1.open(filename);
        if (!out1)
            cout << "That is not a valid file.  Try again!\n";
         } while (!out1);
}
// this function will display each student
void PrintClass (Student* students, ofstream& out1, int size, char subject)
{
    int count = 0;
    double sum = 0;
    char Fullname[40];


    out1 << endl;
    out1 << "Student Name                             Test Avg" << endl;
    out1 << "----------------------------------------------------------------" << endl;

    for( int i = 0; i < size; i++)
    {
        Alphasort(students,size); // EXTRA Credit function

        if (students[i].course == subject)
        {
            strncpy(Fullname,students[i].firstname, 20);
            strncat(Fullname, " ", 1);
            strncat(Fullname, students[i].lastname, 20);
            out1 << setw(44)<< left << Fullname;
            out1 << right << showpoint << fixed << setprecision(2)<< students[i].average << "  " << Grade(students[i]) << endl;
            sum += students[i].average;
            count ++;
        }
    }
    out1 << endl;
    out1 << "     Class Average               " << (sum/count) << endl;
    out1 << "----------------------------------------------------------------" << endl;
    out1 << endl << endl;
}
// This fuction will calculate the test average of the studnts
double TestAverage (const Student& student)
{
    double average;

    average = (student.grade1 * .3) + (student.grade2 * .3) + (student.final * .4);
    return average;
}
// This fuction will display the grades
char Grade (const Student& student)
{
    char grade;

    if (student.average < 60)
        grade = 'F';
    else if (student.average < 70)
        grade = 'D';
    else if (student.average < 80)
        grade = 'C';
    else if (student.average < 90)
        grade = 'B';
    else
        grade = 'A';
    return grade;
}
// Extra Credit: fuction that will alphabetize the last names
void Alphasort (Student* student, int size)
{
    int j, i;

    Student temp;

        for(i = 0; i < size - 1; ++i)
        {
            for(j = i + 1; j < size; ++j)
            {
                if(strcmp(student[i].lastname,student[j].lastname) > 0)
                {
                    temp = student[i];
                    student[i] = student[j];
                    student[j] = temp;
                };
            }
        }
}

[Ancient Dragon]

In Alphasort() you strcmp() is NOT case insensitive. You need to use a case-insensitive function, such as stricmp() or strcasecmp(), depending on the compiler you are using.

Or you could write your own compariso function by copying both strings into a temp variable, convert each to all UPPER case then use strcmp() in the temp strings.

[ana_1234]

Thank you so much. I used stricmp() instead and it worked out perfectly