从类 c++ 动态创建数组

先把这个扔在那里，我还在学校学习如何编程。我在读取动态创建的数组时遇到问题，该数组带有指向我的一个类的指针。函数 readClassArray(( 没有从 student.getCreditNumber 获取变量。该程序在Visual Studio中符合要求，但是当我获得readClassArray时，它只是跳过该函数，因为s.getCreditNumber返回0。

#ifndef STUDENT_H
#define STUDENT_H
#include <iostream>
using namespace std;
class Courses{
private:
int courseNumber;
double hours;
string courseName;
char grade;
public:
void setCourseNumber(int n){courseNumber = n; }
void setCreditHours(double c) { hours = c; }
void setCourseName(string n) { courseName = n; }
void setGrade(char g) { grade = g; }
int getCourseNumber() { return courseNumber; }
double getCreditHours() { return hours; }
string getCourseName() { return courseName; }
char getGrade() { return grade; }
};
class Student : public Courses{
private:
string firstName;
string lastName;
string studentNumber;
int creditNumber;
double gpa;
public:
Courses * courses;
Student() {
firstName = " ";
lastName = " ";
studentNumber = " ";
creditNumber = 0;
gpa = 0.0;
courses = NULL;
}
~Student() {
delete[] courses;
};
void setFirstName(string n) { firstName = n; }
void setLastName(string l) { lastName = l; }
void setStudentNumber(string a) { studentNumber = a; }
void setCreditNumber(int num) { creditNumber = num; }
string getFirstName() { return  firstName; }
string getLastName() { return lastName; }
string getStudentNumber() { return studentNumber; }
int getCreditNumber() { return creditNumber; }
};
#endif

学生.cpp

#include "Student.h"
#include <iostream>
#include <string>
using namespace std;
void readStudent();
void readCourseArray();
void computeGPA();
void printSummary();
void readStudent() {
Student a;
string number;
string firstName;
string lastName;
int courses;
cout << "Enter student number: ";
cin >> number;
a.setStudentNumber(number);
cout << "Enter student first name: ";
cin >> firstName;
a.setFirstName(firstName);
cout << "Enter student last name: ";
cin >> lastName;
a.setLastName(lastName);
cout << "Enter student number of courses: ";
cin >> courses;
a.setCreditNumber(courses);
cout << "n"; }

void readCourseArray(){
Student s;
s.courses = new Courses[s.getCreditNumber()];
int num;
double cHours;
string cName;
char grade;
cout << "test" << endl;
for (int i = 0; i < s.getCreditNumber(); i++){
cout << "Enter class " << i + 1 << " number: ";
cin >> num;
s.courses[i].setCourseNumber(num);
cout << "Enter class " << i + 1 << " name: ";
cin >> cName;
s.courses[i].setCourseName(cName);
cout << "Enter class " << i + 1 << " hours: ";
cin >> cHours;
s.courses[i].setCreditHours(cHours);
cout << "Enter class " << i + 1 << " grade: ";
cin >> grade;
s.courses[i].setGrade(grade);
cout << "n";
}
}