Как сделать работающий код?

package com.javarush.task.task08.task0824; import java.util.ArrayList; import java.util.List; /* Собираем семейство */ public class Solution { public static void main(String[] args) { //напишите тут ваш код Human grandDaddy1= new Human("Igor",true,89,null); Human grandDaddy2= new Human("Vova",true,98,null); Human granny1= new Human("Vala",false,89,null); Human granny2= new Human("Val",false,98,null); Human daddy= new Human("Viktor",true,39,null); Human mom= new Human("Vala",false,89,null); Human child1 = new Human("Lena",false,15,new ArrayList<>()); Human child2 = new Human("Len",false,15,new ArrayList<>()); Human child3 = new Human("Le",false,15,new ArrayList<>()); System.out.println(grandDaddy1.toString()); System.out.println(grandDaddy2.toString()); System.out.println(granny1.toString()); System.out.println(granny2.toString()); System.out.println(daddy.toString()); System.out.println(mom.toString()); System.out.println(child1.toString()); System.out.println(child2.toString()); System.out.println(child3.toString()); } public static class Human { //напишите тут ваш код String name; boolean sex; int age; ArrayList<Human>children; public Human (String name, boolean sex, int age, ArrayList<Human>children) { this.name = name; this.sex = sex; this.age = age; this.children=children; } public String toString() { String text = ""; text += "Имя: " + this.name; text += ", пол: " + (this.sex ? "мужской" : "женский"); text += ", возраст: " + this.age; int childCount = this.children.size(); if (childCount > 0) { text += ", дети: " + this.children.get(0).name; for (int i = 1; i < childCount; i++) { Human child = this.children.get(i); text += ", " + child.name; } } return text; } } }