LRU（Least Recently Used）页面置换算法

LRU（Least Recently Used）页面置换算法——最近最久未使用

数据结构：ArrayDeque双端队列

import java.util.ArrayDeque;
import java.util.Scanner;

public class LRULearn {
    public static void main(String[] args) {
        String Serial = new Scanner(System.in).next();
        LRU lru = new LRU(8);
        lru.VisitPage1(Serial);
        System.out.println(lru.getQueue());
    }
}

class LRU{
    private int Cache;
    private ArrayDeque<Character> queue=new ArrayDeque<>();
    public ArrayDeque<Character> getQueue() {
        return queue;
    }
    public LRU(int cache) {
        Cache = cache;
    }

/*
    public void VisitPage(String Serial){
        for(int i=0;i<Serial.length();i++){
            if(i<Cache){
                queue.addFirst(Serial.charAt(i));
            }
            if(queue.contains(Serial.charAt(i))){
                queue.remove(Serial.charAt(i));

                queue.addFirst(Serial.charAt(i));
            }
            else{
                queue.removeLast();

                queue.addFirst(Serial.charAt(i));
            }
        }
        //System.out.println(queue);
    }
*/

    public void VisitPage1(String Serial){
        for(int i=0;i<Serial.length();i++){
            //先判断满不满
            if (!isFull()){
                if (!queue.contains(Serial.charAt(i))){
                    queue.addFirst(Serial.charAt(i));
                }else {
                    queue.remove(Serial.charAt(i));
                    queue.addFirst(Serial.charAt(i));
                }
            }else {
                if (!queue.contains(Serial.charAt(i))){
                    queue.removeLast();
                    queue.addFirst(Serial.charAt(i));
                }else {
                    queue.remove(Serial.charAt(i));
                    queue.addFirst(Serial.charAt(i));
                }
            }
        }
    }

    public boolean isFull(){
        return queue.size()==Cache;
    }
}