Urkupillit

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main() {
    cin.sync_with_stdio(false);
    cin.tie(0);

    long n, k;
    cin >> n >> k;

    vector<long> u;
    u.reserve(n);
    u.push_back(n);

    for (long i = n - 1; i >= 1; i--) {
        if (k < n - i) {
            u.insert(u.begin() + k, i);
            k = 0;

            std::cout << 1;
            for (long j = 2; j < i; j++) {
                cout << " " << j;
            }

            if (u.size() > 0) {
                for (auto x : u) {
                    cout << " " << x;
                }
            }

            cout << "\n";

            return 0;
        } else {
            k -= n - i;
            u.push_back(i);
        }
    }

    cout << u[0];

    for (long i = 1; i < n; i++) {
        cout << " " << u[i];
    }

    cout << "\n";

    return 0;
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED