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dynamic pointer array

hornet7288 (15)
I am working on a project for class that I am having trouble with. The program creates a class object and sets the class size to 10. However, 13 students are added to the class. I am supposed to change the size of the array to accept 13 students instead of 10. No idea where to start. I have been sitting here for hours trying different things. I was able to get it to generate an error message when the capacity is exceeded and stop the program, but I can't seem to get any further than that. Any help would be greatly appreciated. The lesson today on arrays/pointers was very sub par.

The program runs just fine if I comment out three of the students I am trying to add. So I know my only problem at this point is the array issue. 

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  // Exercise.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <iostream>
#include <string>
using namespace std;

#ifndef COURSE_H
#define COURSE_H
class Course {
public: 
	Course(const string& courseName, int capacity);
	~Course();
	string getCourseName() const;
	void addStudent(const string& name);
	void dropStudent(const string& name);
	string* getStudents() const;
	int getNumberOfStudents() const;
	void clear();

private: 
	string courseName; 
	string* students; 
	int numberOfStudents; 
	int capacity; 

};
#endif

Course::Course(const string& courseName, int capacity) {
	numberOfStudents = 0; 
	this->courseName = courseName; 
	this->capacity = capacity; 
	students = new string[capacity];
}

Course::~Course() {
	delete[] students;
}


string Course::getCourseName() const {
	return courseName;
}

void Course::addStudent(const string& name) {

	students[numberOfStudents] = name;

	numberOfStudents++;

//CANT FIGURE THIS OUT

}

void Course::dropStudent(const string& name) {
	//Find the students name, delete it and shift everything down one spot in the array
	for (int i = 0; i < numberOfStudents; i++) {
		if (students[i] == name) {
			numberOfStudents--;
			for (int j = i + 1; j < numberOfStudents + 1; j++) {
				students[i] = students[j];
			}
		}
	}
}

string* Course::getStudents() const {
	return students;
}

int Course::getNumberOfStudents() const {
	return numberOfStudents;
}

void Course::clear() {
	numberOfStudents = 0;
	
}



int main()
{
	Course course1("Data Structures", 10);
	Course course2("Database Systems", 2);

	course1.addStudent("Peter Jones");
	course1.addStudent("Brian Smith");
	course1.addStudent("Anne Kennedy");
	course1.addStudent("Susan Kennedy");
	course1.addStudent("John Kennedy");
	course1.addStudent("Kim Johnson");
	course1.addStudent("S1");
	course1.addStudent("S2");
	course1.addStudent("S3");
	course1.addStudent("S4");
	course1.addStudent("S5");
	course1.addStudent("S6");
	course1.addStudent("S7");

	course2.addStudent("Peter Jones");
	course2.addStudent("Steve Smith");

	cout << "Number of students in course1: "
		<< course1.getNumberOfStudents() << endl;

	string *students = course1.getStudents();

	for (int i = 0; i < course1.getNumberOfStudents(); i++)
		cout << students[i] << ", ";

	cout << endl;

	cout << "Number of students in course2: " << course2.getNumberOfStudents() << endl;

	course1.dropStudent("S1");
	cout << "Number of students in course1: " << course1.getNumberOfStudents() << endl;

	students = course1.getStudents();

	for (int i = 0; i < course1.getNumberOfStudents(); i++)
		cout << students[i] << ", ";

	cout << endl;
	course1.clear();
	cout << "Number of students in course1: " << course1.getNumberOfStudents() << endl;

	return 0;
}
Last edited on
Bdanielz (506)
Look at line 86. Change the 10 to 13. Does that work?
AbstractionAnon (6954)
Please do not start multiple threads for the same problem.
http://www.cplusplus.com/forum/beginner/197645/

Please see my response in that thread.

hornet7288 (15)
It will make it work, but the idea of the exercise was to make the array so that it adjusts to a higher number.
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