Can't find a solution to a c++ program [closed] - c++

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So I have to write a code for the following program:
Write a program with a main function and menu for choosing a function to:
a) input data for students into an array (faculty number, age, sex) (up to 25)
b) rewrite the data for the male and female students into two new arrays and output the arrays and the average age
c) output the youngest student and make the arrays into ascending order of the age and output the arrays
d) search for a student by a faculty number and output his information
Ok, so far so good. The a) and d) are working as they should, but b) and c) are giving me some trouble. On c) it says the youngest student is -88758375 year-old and it isn't outputting the arrays. And on b) it gives me a logical error and it says Integer division by zero and crashes the program. I really tried to find any mistakes but I'm stuck, so I ask you for some help:)))
#include "stdafx.h"
#include <iostream>
using namespace std;
const int N = 25;
struct student
{
int fN;
int age;
char sex;
};
// a)
void input(student fN[N], int numberOfStudents)
{
for (int i = 0; i<numberOfStudents; i++)
{
cout << "Faculty number: ";
cin >> fN[i].fN;
cout << "Age: ";
cin >> fN[i].age;
cout << "Sex: ";
cin >> fN[i].sex;
cout << endl;
}
}
// b)
void rearrange(student fN[N], student fNm[N], student fNf[N], int numberOfStudents, int m, int f)
{
int avgAgeM = 0, avgAgeF = 0;
for (int i = 0; i < numberOfStudents; i++)
{
if (fN[i].sex == 'm')
{
fNm[m].fN = fN[i].fN;
fNm[m].age = fN[i].age;
fNm[m].sex = fN[i].sex;
m++;
avgAgeM = avgAgeM + fN[i].age;
}
else if (fN[i].sex == 'f')
{
fNf[f].fN = fN[i].fN;
fNf[f].age = fN[i].age;
fNf[f].sex = fN[i].sex;
f++;
avgAgeF = avgAgeF + fN[i].age;
}
cout << endl;
for (int i = 0; i < m; i++)
{
cout << "\tFaculty number: " << fNm[i].fN << "\tAge: " << fNm[i].age << "\tSex: " << fNm[i].sex << endl;
}
cout << "Average male age: " << avgAgeM / m << "\n\n";
for (int i = 0; i<f; i++)
{
cout << "\tFaculty number: " << fNf[i].fN << "\tAge: " << fNf[i].age << "\tSex: " << fNf[i].sex << endl;
}
cout << "Average female age: " << avgAgeF / f << "\n\n";
}
}
// c)
void ascendingAge(student fNm[N], student fNf[N], int m, int f)
{
int x, y;
char z;
for (int i = 0; i < m-1; i++)
for (int j = 0; j < m-i-1; j++)
{
if (fNm[j].age > fNm[j + 1].age)
{
x = fNm[j].age;
y = fNm[j].fN;
z = fNm[j].sex;
fNm[j + 1].age = fNm[j].age;
fNm[j].age = x;
fNm[j + 1].fN = fNm[j].fN;
fNm[j].fN = y;
fNm[j + 1].sex = fNm[j].sex;
fNm[j].sex = z;
}
}
for (int i = 0; i < f-1; i++)
for (int j = 0; j < f-i-1; j++)
{
if (fNf[j].age > fNf[j + 1].age)
{
x = fNf[j].age;
y = fNf[j].fN;
z = fNf[j].sex;
fNf[j + 1].age = fNf[j].age;
fNf[j].age = x;
fNf[j + 1].fN = fNf[j].fN;
fNf[j].fN = y;
fNf[j + 1].sex = fNf[j].sex;
fNf[j].sex = z;
}
}
cout << "The youngest female student is " << fNf[0].age << " year-old." << endl;
for (int i = 0; i < m; i++)
cout << "\tFaculty number: " << fNm[i].fN << "\tAge: " << fNm[i].age << "\tSex: " << fNm[i].sex << endl;
for (int i = 0; i<f; i++)
cout << "\tFaculty number: " << fNf[i].fN << "\tAge: " << fNf[i].age << "\tSex: " << fNf[i].sex << endl;
cout << endl;
}
//d
void searchStudent(student fN[N], int numberOfStudents)
{
int x, index;
bool yes = false;
cout << "Enter a faculty number: ";
cin >> x;
for (int i = 0; i < numberOfStudents; i++)
if (fN[i].fN == x)
{
yes = true;
index = i;
}
cout << endl;
if (yes == true)
cout << "\tFaculty number: " << fN[index].fN << "\tAge: " << fN[index].age << "\tSex: " << fN[index].sex << endl;
else
cout << "No such faculty number.\n\n";
}
int main()
{
student fN[N], fNm[N], fNf[N];
int numberOfStudents, m = 0, f = 0;
char check;
cout << "Enter number of students: ";
cin >> numberOfStudents;
BACK:
cout << "\n\n";
cout << "\t a) \n\t b) \n\t c) \n\t d)\n Press'q' to exit.\n\n";
cin >> check;
switch (check)
{
case 'a':
input(fN, numberOfStudents);
goto BACK;
break;
case 'b':
rearrange(fN, fNm, fNf, numberOfStudents, m, f);
goto BACK;
break;
case 'c':
ascendingAge(fNm, fNf, m, f);
goto BACK;
break;
case 'd':
searchStudent(fN, numberOfStudents);
goto BACK;
break;
case 'q':
return 0;
break;
default:
cout << "Wrong input.\n";
goto BACK;
}
system("pause");
return 0;
}

Answer 1

In the function rearrange you need pass m and k by reference:
void rearrange(student fN[N], student fNm[N], student fNf[N], int numberOfStudents, int& m, int& f):
Оr they will not be changed

Answer 2

You seem to want m and f to be outputs from this function
void rearrange(student fN[N], student fNm[N], student fNf[N], int numberOfStudents, int m, int f)
but that would work only if passed by reference:
void rearrange(student fN[N], student fNm[N], student fNf[N], int numberOfStudents, int& m, int& f)
You should guard against divide by zero by testing. Instead of:
cout << "Average male age: " << avgAgeM / m << "\n\n";
use
if (m)
cout << "Average male age: " << avgAgeM / m << "\n\n";
else
cout << "There are zero males\n\n";
and similarly for f