Java思路：使用String的字符串处理以及ArrayList的列表处理。

Java代码：

import java.util.ArrayList;
import java.util.Scanner;
public class Main{public static ArrayList<String> list = new ArrayList<>();public static void main(String[] args) {Scanner sc = new Scanner(System.in);int n = sc.nextInt();String s = sc.nextLine();for (int i = 0; i < n; i++) {String str = sc.nextLine();String[] strArr = str.split(" ");if ("ls".equals(strArr[0])){for (int j = 0; j < list.size(); j++) {System.out.println(list.get(j));}}else if ("rm".equals(strArr[0]) && list.indexOf(strArr[1]) != -1){list.remove(list.indexOf(strArr[1]));}else if ("touch".equals(strArr[0]) && list.indexOf(strArr[1]) == -1){list.add(strArr[1]);}else rename(strArr[1],strArr[2]);}}public static void rename(String fromName,String toName){if (list.indexOf(fromName) == -1){list.add(toName);}else {list.set(list.indexOf(fromName),toName);}}
}