영상
개념
package 콜렉션종류_개념;
import java.util.ArrayList;
import java.util.Scanner;
public class 콜렉션종류_기본이론1_어레이리스트2 {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
ArrayList<Integer> list = new ArrayList<>();
while(true) {
System.out.println(list);
System.out.println("1.추가 2.삭제 3.삽입 4.종료");
int sel = scan.nextInt();
if(sel == 1) {
System.out.println("추가할 숫자를입력하세요 >> ");
int num = scan.nextInt();
list.add(num);
}else if(sel == 2) {
System.out.println(list);
System.out.println("삭제할 인덱스를 입력하세요 >> ");
int index = scan.nextInt();
if(list.size() <= 0) {
continue;
}
if(index < 0) {
continue;
}
if(index >= list.size()) {
continue;
}
list.remove(index);
}else if(sel == 3) {
System.out.println(list);
System.out.println("삽입할 위치를 입력하세요 >> ");
int pos = scan.nextInt();
System.out.println("삽입할 값을 입력하세요 >> ");
int value = scan.nextInt();
list.add(pos , value);
}
else if(sel == 4) {
System.out.println("종료");
break;
}
}
scan.close();
}
}
Java
복사