C++ help. I am having difficulty understanding pointers within function prototyp

Question

C++ help. I am having difficulty understanding pointers within function prototypes and structures. I understand the code withing the struc and func itself. I just am confused about how to get the information in main. Here is my programming exercise:

Change the declaration of

Student freshman;

to

Student *freshman'

Dynalmically allowcate a Student object and then fix the rest of the program to work. Make sure to use delete properly.

// This program demonstrates a function that uses a
// pointer to a structure variable as a parameter.
#include <iostream>
#include <string>
#include <iomanip>
using namespace std;

struct Student
{
   string name;              // Student's name
   int idNum;             // Student ID number
   int creditHours;       // Credit hours enrolled
   double gpa;              // Current GPA
};

void getData(Student *); // Function prototype

int main()
{
   Student freshman;

   // Get the student data.
   cout << "Enter the following student data: ";
   getData(&freshman);    // Pass the address of freshman.
   cout << " Here is the student data you entered: ";

   // Now display the data stored in freshman
   cout << setprecision(3);
   cout << "Name: " << freshman.name << endl;
   cout << "ID Number: " << freshman.idNum << endl;
   cout << "Credit Hours: " << freshman.creditHours << endl;
   cout << "GPA: " << freshman.gpa << endl;
   return 0;
}

//*******************************************************
// Definition of function getData. Uses a pointer to a *
// Student structure variable. The user enters student *
// information, which is stored in the variable.        *
//*******************************************************

void getData(Student *s)
{
   // Get the student name.
   cout << "Student name: ";
   getline(cin, s->name);

   // Get the student ID number.
   cout << "Student ID Number: ";
   cin >> s->idNum;

   // Get the credit hours enrolled.
   cout << "Credit Hours Enrolled: ";
   cin >> s->creditHours;

   // Get the GPA.
   cout << "Current GPA: ";
   cin >> s->gpa;
}

Explanation / Answer

// This program demonstrates a function that uses a
// pointer to a structure variable as a parameter.
#include <iostream>
#include <string>
#include <iomanip>
using namespace std;
struct Student
{
string name; // Student's name
int idNum; // Student ID number
int creditHours; // Credit hours enrolled
double gpa; // Current GPA
};
void getData(Student *); // Function prototype
int main()
{
Student *freshman;

//Dynamically allocating memory for freshman
freshman = new Student;
// Get the student data.
cout << "Enter the following student data: ";
getData(freshman); // Pass the address of freshman.
cout << " Here is the student data you entered: ";
// Now display the data stored in freshman
cout << setprecision(3);
cout << "Name: " << freshman->name << endl;
cout << "ID Number: " << freshman->idNum << endl;
cout << "Credit Hours: " << freshman->creditHours << endl;
cout << "GPA: " << freshman->gpa << endl;
//deleting dynamically allocated memory
delete freshman;
return 0;
}
//*******************************************************
// Definition of function getData. Uses a pointer to a *
// Student structure variable. The user enters student *
// information, which is stored in the variable. *
//*******************************************************
void getData(Student *s)
{
// Get the student name.
cout << "Student name: ";
getline(cin, s->name);
// Get the student ID number.
cout << "Student ID Number: ";
cin >> s->idNum;
// Get the credit hours enrolled.
cout << "Credit Hours Enrolled: ";
cin >> s->creditHours;
// Get the GPA.
cout << "Current GPA: ";
cin >> s->gpa;
}

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