第一张截图里se.nextLine() 为什么要写两次呢?两次分别是什么意思呢?mian方法中(用equals方法比较该对象是否已经在数组中存在)又该怎么写呢?如何应用ArrayList来简化代码呢?
```java
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Objects;
import java.util.Scanner;
public class Main{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int n1= sc.nextInt();
boolean f=true;
sc.nextLine();
ArrayList<PersonOverride> ap=new ArrayList<PersonOverride>();
for (int i=0;i<n1;i++){
ap.add(new PersonOverride());
}
int n2= sc.nextInt();
sc.nextLine();
for (int i=0;i<n2;i++){
f=true;
PersonOverride a=new PersonOverride(sc.next(),sc.nextInt(), sc.nextBoolean());
sc.nextLine();
for (PersonOverride aa:ap) {
if (aa.equals(a)){
f=false;
break;
}
}
if (f)ap.add(a);
}
for(PersonOverride a:ap){
System.out.println(a.toString().replace("[","").replace("]",""));
}
System.out.println(ap.size()-n1);
System.out.println(Arrays.toString(PersonOverride.class.getConstructors()));
}
}
class PersonOverride{
private String name;
private int age;
private boolean gender;
public PersonOverride() {
this("default",1,true);
}
public PersonOverride(String name, int age, boolean gender) {
this.name = name;
this.age = age;
this.gender = gender;
}
@Override
public String toString() {
return name + "-" + age + "-" + gender;
}
@Override
public boolean equals(Object o) {
if (this == o)
return true;
if (o == null || getClass() != o.getClass())
return false;
PersonOverride that = (PersonOverride) o;
return age == that.age &&
gender == that.gender &&
name.equals(that.name);
}
@Override
public int hashCode() {
return Objects.hash(name, age, gender);
}
}
```