Классы С++

#include <iostream.h>
#include <conio.h>
#include <tchar.h>
 
class Human {
    public:
    Human();
    int x, z;
    int calculate(int x, int z);
};
 
int Human::calculate(int x, int z)
{
    x * 10 == z;
    return z;
};
 
 
int _tmain(int argc, _TCHAR* argv[])
{
    Human height;
    cout << "Height in sm - " << endl;
    cin >> height.x;
    height.calculate(int x, int z);
    cout << "Height in mm - " << endl;
    cin >> height.z >> endl;
    getch();
 
}

#include <iostream>
#include <conio.h>
#include <tchar.h>
 
class Human {
        public:
        int x, z;
        int calculate(int x);
};
 
int Human::calculate(int x)
{
        return x*10;
}
 
 
int main()
{
        Human height;
        std::cout << "Height in sm - " << std::endl;
        std::cin >> height.x;
        height.z = height.calculate(height.x);
        std::cout << "Height in mm - " << std::endl;
        std::cout << height.z << std::endl;
        system ("pause");
}

using namespace std;

namespace TextLib {
class Text { /*...*/};
class Glyph {/*...*/};
class Line{/*...*/};
}

std:: ofstream ofs ("output.txt");
ofs << 123 << "\n";