C++ basics

example.cpp

#include "examples.h"
#include <vector>


bool changeAge(std::vector<Person>& people) {

    // Create people
    for (int i = 0; i < 50; i++) {
        Person new_person;
        new_person.gender = Gender::Male;
        people.push_back(new_person);
    }

    // Set age
    for (auto &it = people.begin(); it != people.end(); it++) {
        it->age = 20;
    }
    return true;
}

bool changeName(std::vector<Person>& people) {
    for (auto &it = people.begin(); it != people.end(); it++) {
        it->name = "Jenna";
    }
    return true;
}


void displayPeopleData(std::vector<Person>& people) {
    for (unsigned int i = 0; i < people.size(); ++i) {
        fprintf(stdout, "%d | Name: %s, Age: %d, Gender %d\n", i, people[i].name.c_str(), people[i].age, people[i].gender);
    }
    std::cin.ignore(std::numeric_limits <std::streamsize>::max(), '\n'); // Wait user to press enter.
}

int main()
{
    std::vector<Person> people; 


    people = people;

    changeAge(people);

    people = people;

    changeName(people);

    people = people;

    displayPeopleData(people);

	return EXIT_SUCCESS;
}

example.h

#pragma once

#include <iostream>

enum class Gender {
    Female = 0,
    Male   = 1,
};


struct Person {
    unsigned int age;
    std::string name;
    Gender gender;
};