Understanding Classes.

[Pebble]

After running the following program but have a couple of question's:

1. The first line in main is: Person people[128] does this allocate space for
128 entries in class Person?

2. The first fuction has the line Person person.
I presume the first Person refers to the class Person, Does the second
person give a name to the array?


#include <iostream>
#include <cstdlib>
#include <cstdio>

class Person
{
public:
char szFirstName[128];
char szLastName[128];
int nSocialSecurityNumber;
};

Person getPerson()
{
Person person;
std::cout << "\nEnter another person\n" << "First name: ";
std::cin >> person.szFirstName;
std::cout << "Last name: ";
std::cin >> person.szLastName;
std::cout << "Social Security number: ";
std:: cin >> person.nSocialSecurityNumber;
return person;
}

int getPeople(Person people[], int nMaxSize)
{
int index;
for(index = 0; index < nMaxSize; index++)
{
char cAnswer;
std::cout << "Enter another name? (Y or N)";
std::cin >> cAnswer;
if (cAnswer != 'Y' && cAnswer != 'y')
{
break;
}
people[index] = getPerson();
}
return index;
}

void displayPerson(Person person)
{
std::cout << "First name: " << person.szFirstName << std::endl;
std::cout << "Last name : " << person.szLastName << std::endl;
std::cout << "Social Security number : " << person.nSocialSecurityNumber << std::endl;
}

void displayPeople(Person people[], int nCount)
{
for(int index = 0; index < nCount; index++)
{
displayPerson(people[index]);
}
}

void sortPeople(Person people[], int nCount)
{
int nSwaps = 1;
while(nSwaps != 0)
{
nSwaps = 0;
for(int n = 0; n < (nCount - 1); n++)
{
if (people[n].nSocialSecurityNumber > people[n + 1].nSocialSecurityNumber)
{
Person temp = people[n + 1];
people[n + 1] = people[n];
people[n] = temp;
nSwaps++;
}
}
}
}

int main(int nNumberofArgs, char* pszArgs[])
{
Person people[128];
std::cout << "Read name/social security information\n";
int nCount = getPeople(people, 128);
sortPeople(people, nCount);
std::cout << "\nHere is the list sorted by " << "social security number" << std::endl;
displayPeople(people, nCount);
return 0;
}

[eraggo]

Use code tags, Please.
Here:

#include <iostream>
#include <cstdlib>
#include <cstdio>

class Person
{
public:
	char szFirstName[128];
	char szLastName[128];
	int nSocialSecurityNumber;
};

Person getPerson()
{
	Person person;
	std::cout << "\nEnter another person\n" << "First name: ";
	std::cin >> person.szFirstName;
	std::cout << "Last name: ";
	std::cin >> person.szLastName;
	std::cout << "Social Security number: ";
	std::cin >> person.nSocialSecurityNumber;
	return person;
}

int getPeople(Person people[], int nMaxSize)
{
	int index;
	for(index = 0; index < nMaxSize; index++)
	{
		char cAnswer;
		std::cout << "Enter another name? (Y or N)";
		std::cin >> cAnswer;
		if (cAnswer != 'Y' && cAnswer != 'y')
		{
			break;
		}
	people[index] = getPerson();
	}
	return index;
}

void displayPerson(Person person)
{
	std::cout << "First name: " << person.szFirstName << std::endl;
	std::cout << "Last name : " << person.szLastName << std::endl;
	std::cout << "Social Security number : " << person.nSocialSecurityNumber << std::endl;
}

void displayPeople(Person people[], int nCount)
{
	for(int index = 0; index < nCount; index++)
{

displayPerson(people[index]);
}
}

void sortPeople(Person people[], int nCount)
{
	int nSwaps = 1;
	while(nSwaps != 0)
	{
		nSwaps = 0;
		for(int n = 0; n < (nCount - 1); n++)
		{
			if (people[n].nSocialSecurityNumber > people[n + 1].nSocialSecurityNumber)
			{
				Person temp = people[n + 1];
				people[n + 1] = people[n];
				people[n] = temp;
				nSwaps++;
			}
		}
	}
}

int main(int nNumberofArgs, char* pszArgs[])
{
	Person people[128];
	std::cout << "Read name/social security information\n";
	int nCount = getPeople(people, 128);
	sortPeople(people, nCount);
	std::cout << "\nHere is the list sorted by " << "social security number" << std::endl;
	displayPeople(people, nCount);
	return 0;
}

[MiiNiPaa]

1) Yes.
2) It declares a variable named person of type Person

[Pebble]

Thank's MiiNiPaa.

[Fransje]

1) Not space for 128 entries in class Person, but space for 128 instances of class Person.