请选出以下程序的输出结果 public class Child extends People { People father; public Child(String name) { System.out.print(3); this.name = name; father = new People(name + ":F"); } public Child() { System.out.print(4); } public static void main(String[] args) { new Child("Alice"); } } class People { String name; public People() { System.out.print(1); } public People(String name) { System.out.print(2); this.name = name; } }