题解 | #【模板】循环队列#

1.import java.util.Scanner;

public class Main {

public static void main(String[] args) {
	// TODO Auto-generated method stub
	 Scanner scan = new Scanner(System.in) ;
	    int n1 = scan.nextInt();
        int n2 = scan.nextInt();
        
        Quene1 q = new Quene1(n1+1) ;
        
        while(scan.hasNextLine()){
        	String s = scan.nextLine() ;
            String arr[] = s.split(" ") ;
            
           if(arr[0].equals("push")) {
                q.push(Integer.parseInt(arr[1])) ;
            } else if(arr[0].equals("pop")) {
                q.pop() ;
            } else if(arr[0].equals("front")){
                q.top() ;
            }
      }		
}

}

class Quene1 { int[] arr ; int maxSize ; int front;//头部 int rear;//尾部

public Quene1(int maxSize) {
    this.maxSize = maxSize ;
    arr = new int[maxSize] ;
    front = 0;
    rear = 0;
}
//加数据
public void push(int val) {
    if((rear+1)%maxSize==front) {
        System.out.println("full") ;
    } else {
       arr[rear] = val;
       rear = (rear+1)%maxSize;
    }
}
//取头部数据
public void top() {
    if(rear==front) {
        System.out.println("empty") ;
    } else {
        System.out.println(arr[front]);
    }
}
//取数据
public void pop() {
    if(rear==front) {
        System.out.println("empty") ;
    } else {           
    	int value = arr[front];
		front = (front+1)%maxSize;
        System.out.println(value);
        
    }
}
//

}