13 контест Александру

// 1

#include <iostream>
#include <vector>

using namespace std;

int const FACTORIAL[13] =
        {
                1, 1, 2,
                6, 24, 120,
                720, 5040, 40320,
                362880, 3628800, 39916800,
                479001600
        };


class Task {
    vector<int> res_perm;
    vector<bool> used;

public:

    Task(int n) {
        res_perm.resize(n);
        used.resize(n + 1);
    }

    void solve(int n, int k) {
        for (int i = 0; i < n; i++) {
            int j = 1, pos = 0, skip = 1 + (k - 1) / FACTORIAL[n - i - 1];
            for (; j <= n; j++) {
                if (!used[j]) {
                    pos += 1;
                }
                if (skip == pos) {
                    break;
                }
            }
            k = 1 + (k - 1) % FACTORIAL[n - i - 1];
            res_perm[i] = j;
            used[j] = true;
        }
        for (auto &i: res_perm)
            cout << i << ' ';
    }

};

int main() {
    int n, k;
    cin >> n >> k;
    Task task(n);
    task.solve(n, k);
    return 0;
}

//2

#include <iostream>
#include <vector>

using namespace std;



class Task{

    vector<int> answer;

public:

    void solve(int i, int n, int k) {
        if (k == 0) {
            for (auto &i : answer)
                cout << i << " ";
            cout << endl;
        } else {
            for (int j = i; j <= n - k; j++) {
                answer.push_back(j + 1);
                solve(j + 1, n, k - 1);
                answer.pop_back();
            }
        }
    }
};

int main() {
    int n, k;
    cin >> n >> k;

    Task task;
    task.solve(0, n, k);

    return 0;
}

//3

#include <iostream>
#include <vector>

using namespace std;


class Task {

    vector<int> answer;
    vector<bool> used;

public:


    Task(int n, int k){
        answer.resize(k);
        used.resize(n);
    }

    void solve(int n, int k, int m) {
        int a = n - 1,  b = k - 1;
        for (int i = 0; i < k; i++) {
            int amount = 1;
            for (int j = a; j >= a - b + 1; j--) {
                amount *= j;
            }
            a--;
            b--;
            int block = m / amount, position = 0;
            m -= block * amount;
            block++;
            while (block) {
                if (!used[position]) {
                    block--;
                }
                position++;
            }
            answer[i] = position;
            used[position - 1] = true;
        }

        for (auto &i : answer)
            cout << i << " ";
    }
};

int main() {
    int n, k, m;
    cin >> n >> k >> m;
    Task task(n, k);
    task.solve(n, k, m - 1);

    return 0;
}