코드

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Main {
    static int N;
    static long count = 0, k;
    static boolean[] visit;

    public static void main(String[] args) throws IOException {
        //initialize
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        N = Integer.parseInt(br.readLine());
        visit = new boolean[N + 1];
        StringTokenizer st = new StringTokenizer(br.readLine());

        int problemNum = Integer.parseInt(st.nextToken());

        if (problemNum == 1) {
            System.out.println(ansOfProblemOne(st));
        } else {
            System.out.println(ansOfProblemTwo(st));
        }
    }

    private static String ansOfProblemOne(StringTokenizer st) {
        k = Long.parseLong(st.nextToken());
        int[] ans = new int[N];

        long toAdd = getFactorial(N - 1);

        createSet(0, ans);

        //print
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < N; i++) {
            sb.append(ans[i]).append(" ");
        }
        return sb.toString();
    }

    private static void createSet(int depth, int[] ans) {
        if (depth == N) return;

        long toAdd = getFactorial(N - 1 - depth);

        for (int i = 1; i <= N; i++) {
            if (visit[i]) continue;

            count += toAdd;

            if (count < k) continue;

            ans[depth] = i;
            visit[i] = true;
            count -= toAdd;
            createSet(depth + 1, ans);
            break;
        }
    }

    private static String ansOfProblemTwo(StringTokenizer st) {
        int[] set = new int[N];
        long count = 1;

        for (int i = 0; i < N; i++) {
            set[i] = Integer.parseInt(st.nextToken());
        }

        for (int i = 0; i < N; i++) {
            long toAdd = getFactorial(N - 1 - i);

            visit[set[i]] = true;

            for (int num = 1; num <= set[i]; num++) {
                if (visit[num]) continue;
                count += toAdd;
            }
        }

        return Long.toString(count);
    }

    private static long getFactorial(int n) {
        long ans = 1;

        for (int i = 1; i <= n; i++) {
            ans *= i;
        }

        return ans;
    }
}

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