题解 | #扭蛋机#

import java.util.List;
import java.util.Scanner;

public class Main {
    static List<String> rsList = new ArrayList<String>();
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        f(n, new ArrayList<>());
        for (String s : rsList) {
            System.out.print(s);
        }
    }

    private static int f(int n, List<String> sList) {
        List<String> copyList = new ArrayList<>(sList);
        if(n == 1){
            sList.add(0, "2");
            rsList = sList;
            return 1;
        }
        if(n == 2){
            sList.add(0, "3");
            rsList = sList;
            return 1;
        }
        if (n % 2 == 0) {
            copyList.add(0, "3");
            return f((n - 2) / 2, copyList) + 1;
        } else {
            copyList.add(0, "2");
            return f((n - 1) / 2, copyList) + 1;
        }
    }
}