Output comes out wrong - c++

Question

I am teaching myself C/C++ at the moment, and I got the exercise (from the book I am reading) to write a program that could make an output like this:
Enter your first name: Flip
Enter your last name: Fleming
Here’s the information in a single string: Fleming, Flip
Using Structures. But my output comes out like this:
Enter your first name: Flip
Enter your last name: Fleming
Here’s the information in a single string: ,
Here is the code. It's fairly short and simple so it shouldn't be hard to read :)
#include <iostream>
#include <cstring>
using namespace std;
struct Person {
char* firstName;
char* lastName;
};
char* getName(void);
int main() {
Person* ps = new Person;
cout << "Enter your first name: ";
char* name;
name = getName();
ps->firstName = name;
cout << "Enter your last name: ";
char* lastname;
lastname = getName();
ps->lastName = lastname;
cout << "Here's the information in a single string: "
<< ps->lastName << ", " << ps->firstName;
delete ps;
delete name;
delete lastname;
return 0;
}
char* getName() {
char temp[100];
cin >> temp;
cin.getline(temp, 100);
char* pn = new char[strlen(temp) + 1];
strcpy(pn, temp);
return pn;
}

Answer 1

First, there's no such thing as C/C++. You're mixing them, which is wrong. Since you're using C++ headers/new/using, I'll assume you want C++, so here's how you fix your code:
replace all char* and char[] with std::string
get rid of dynamic allocation
So, some changes would be:
struct Person {
std::string firstName;
std::string lastName;
};
or
Person ps;

Answer 2

You are using:
cin >> temp;
cin.getline(temp, 100);
You probably overwrite what you already have with empty string at the end of a line.
Use just one of them.
If you'll stick with using cin >> you may consider setting width() to prevent buffer overflow.

Answer 3

First, the immediate problem is that you read twice from std::cin: first with operator>>, and then with getline. Pick one or the other.
But let's simplify your code a bit. There are simply too many sources of error. Pointers are tricky because they might point to the wrong thing, or you might forget to delete objects, or delete them twice. C-style char arrays as strings are bad because, well, they're not strings, and they don't behave like strings.
So let's use the standard library's string class:
#include <iostream>
#include <string>
struct Person {
std::string firstName;
std::string lastName;
};
std::string getName(void);
int main() {
Person ps;
cout << "Enter your first name: ";
std::string name = getName();
ps.firstName = name;
cout << "Enter your last name: ";
std::string lastname = getName();
ps.lastName = lastname;
cout << "Here's the information in a single string: "
<< ps.lastName << ", " << ps.firstName;
}
std::string getName() {
std::string temp;
std::getline(cin, temp);
return temp;
}
This is a fairly simple, almost mechanical substitution, basically just replacing char* by std::string, and removing the bits that are no longer necessary.
Of course, as pointed out in a comment, I've omitted all forms of error checking, which a real program should definitely do.

Answer 4

No no no, wayyyy too complicated. Use real C++ idioms. The program could be as simple as this:
#include <string>
#include <iostream>
int main()
{
std::string firstName, lastName;
if (!(std::cout << "Your first name: " &&
std::getline(std::cin, firstName) &&
std::cout << "Your last name: " &&
std::getline(std::cin, lastName) ))
{
std::cerr << "Error: unexpected end of input!\n";
return 0;
}
std::cout << "You are " << firstName << " " << lastName << ".\n";
}
As a variation on the theme, you could put each getline in a loop until the user inputs a non-empty line:
std::cout >> "Your first name: ";
for ( ; ; )
{
if (!(std::getline(std::cin, firstName))
{
std::cerr << "Error: unexpected end of input.\n";
return 0;
}
if (!firstName.empty())
{
break;
}
std::cout << "Sorry, please repeat - your first name: ";
}