Что не так?

package com.javarush.task.task08.task0824; /* Собираем семейство */ import java.util.ArrayList; public class Solution { public static void main(String[] args) { //напишите тут ваш код ArrayList<Human> children = new ArrayList<>(); children.add(new Human("ch1", true, 10)); children.add(new Human("ch2", false, 12)); children.add(new Human("ch3", true, 15)); System.out.println(children.toString()); ArrayList<Human> perents1 = new ArrayList<>(); ArrayList<Human> perents2 = new ArrayList<>(); perents1.add(new Human("m", false, 30, children)); perents2.add(new Human("f", true, 35, children)); System.out.println(perents1.toString()); System.out.println(perents2.toString()); ArrayList<Human> gperents = new ArrayList<>(); gperents.add(new Human("gf1", true, 55, perents1)); gperents.add(new Human("gf2", true, 55, perents2)); gperents.add(new Human("gm1", false, 50, perents1)); gperents.add(new Human("gm2", false, 50, perents2)); System.out.println(gperents.toString()); } public static class Human { //напишите тут ваш код String name; Boolean sex; int age; ArrayList<Human> children = new ArrayList<>(); Human (String name, boolean sex, int age) { this.name = name; this.sex = sex; this.age = age; } 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; } } }