разработать программу, которая будет использовать структуру в С

#include <stdio.h>
#include <cstdlib>
 
struct human
{
private:
    char *_surname;
    char *_name;
    int _age;
public:
    human(char *surname, char *name, int age)
    {
        this->_surname = surname;
        this->_name = name;
        this->_age = age;
    }
    void show()
    {
        printf("\nInfo:\nSurname : %s\nName : %s\nAge : %d\n", this->_surname, this->_name, this->_age);
    }
};
 
int main()
{
    human Human("Doe", "John", 22);
    Human.show();
    system("pause");
    return 0;
}

#include <stdio.h>
#include <cstdlib>
 
struct human
{
private:
    char *_surname;
    char *_name;
    int _age;
public:
    human(char *surname, char *name, int age)
    {
        this->_surname = surname;
        this->_name = name;
        this->_age = age;
    }
    void show()
    {
        printf("\nInfo:\nSurname : %s\nName : %s\nAge : %d\n", this->_surname, this->_name, this->_age);
    }
};
 
int main()
{
    human Human("Doe", "John", 22);
    Human.show();
    system("pause");
    return 0;
}

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <random>
 
struct human
{
private:
    char *_surname;
    char *_name;
    int _age;
public:
    human()
    {
        this->_surname = 0;
        this->_name = 0;
        this->_age = 0;
    }
    human(char *surname, char *name, int age)
    {
        this->_surname = surname;
        this->_name = name;
        this->_age = age;
    }
    void show()
    {
        printf("Person : %s %s, %d years old\n", this->_surname, this->_name, this->_age);
    }
    int GetAge()
    {
        return this->_age;
    }
};
 
int main()
{
    const int N = 10;
 
    srand(time(NULL));
 
    double age_sum = 0.0;
    human Humans[N];
    for(int i = 0; i < N; i++)
    {
        //random from 10 up to 80
        Humans[i] = human("Name", "Surname", rand() % (80 - 10 + 1) + 10);
        age_sum += Humans[i].GetAge();
        Humans[i].show();
    }
 
    
    printf("\nAverage age is = %lf\n", age_sum / N);
    system("pause");
    return 0;
}