题解 | #【模板】循环队列#
【模板】循环队列
https://www.nowcoder.com/practice/0a3a216e50004d8bb5da43ad38bcfcbf
import java.util.*; // 注意类名必须为 Main, 不要有任何 package xxx 信息 public class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); // 注意 hasNext 和 hasNextLine 的区别 int size = in.nextInt(); int a = in.nextInt(); List<Integer> queue = new ArrayList<>(size); in.nextLine(); for(int i = 0;i < a; i++){ String input = in.nextLine(); if(input.startsWith("push")){ if(queue.size() == size){ System.out.println("full"); }else{ String[] operate = input.split(" "); queue.add(0,Integer.parseInt(operate[1])); } }else if(input.startsWith("pop")){ if(queue.isEmpty()){ System.out.println("empty"); }else{ System.out.println(queue.get(queue.size()-1)); queue.remove(queue.size()-1); } }else{ if(queue.isEmpty()){ System.out.println("empty"); }else{ System.out.println(queue.get(queue.size()-1)); } } } } }