#include <iostream>

using namespace std;

struct Letter {
    int index, house, room;
    string name, city, street;
};

void sentLetter(Letter letter) {
    postOffice.addNewLetter(letter);
    return;
}

struct Animal {
    string name;
    int type;
    union {
        string color; // if dog or cat
        int years; // if turtle
        int height; // if giraffe
    } config;
};