How to use main variable in functions? - c++

Question

I got a function but i can't define any variable inside and global too. This function gets a char value from user. I need to define this value to main function. How can i do it? Thanks for helping guys.
This is my code. I made it like this but I define variables in global but I need to define this variables in only main.
#include <iostream>
using namespace std;
char cName[255], cSurname[255];
bool nameFunc() {
cout << "Whats Your Name ?\n";
cin >> cName;
if (cName != NULL && cName[0] == '\0') {
return false;
}
else {
return true;
}
}
bool surnameFunc() {
cout << "Whats Your Surname ?\n";
cin >> cSurname;
if (cSurname != NULL && cSurname[0] == '\0') {
return false;
}
else {
return true;
}
}
int main() {
if (nameFunc() and surnameFunc()) {
cout << "Hello, " << cName << " " << cSurname << "." << endl;
}
else {
cout << "Error! Name or Surname is empty." << endl;
}
system("PAUSE");
return 0;
}

Answer 1

You could pass references to your variables to the functions. Since the char[] have a fixed length, you need to make sure that you don't write out-of-bounds which complicates things.
Example:
#include <iostream>
template<size_t N>
bool nameFunc(char (&cName)[N]) {
std::cout << "Whats Your Name ?\n";
std::cin.getline(cName, N); // read at most N chars
return cName[0] != '\0';
}
template<size_t N>
bool surnameFunc(char (&cSurname)[N]) {
std::cout << "Whats Your Surname ?\n";
std::cin.getline(cSurname, N); // read at most N chars
return cSurname[0] != '\0';
}
int main() {
char cName[255], cSurname[255];
if (nameFunc(cName) and surnameFunc(cSurname)) {
std::cout << "Hello, " << cName << " " << cSurname << ".\n";
}
else {
std::cout << "Error! Name or Surname is empty.\n";
}
}
A much easier option would be to use std::strings and pass them by reference to the functions.

Answer 2

Is it what you're looking for?
#include <iostream>
using namespace std;
bool nameFunc(char* cName) {
cout << "Whats Your Name ?\n";
cin >> cName;
if (cName != NULL && cName[0] == '\0') {
return false;
}
else {
return true;
}
}
bool surnameFunc(char* cSurname) {
cout << "Whats Your Surname ?\n";
cin >> cSurname;
if (cSurname != NULL && cSurname[0] == '\0') {
return false;
}
else {
return true;
}
}
int main() {
char cName[255], cSurname[255];
if (nameFunc(cName) and surnameFunc(cSurname)) {
cout << "Hello, " << cName << " " << cSurname << "." << endl;
}
else {
cout << "Error! Name or Surname is empty." << endl;
}
system("PAUSE");
return 0;
}