const ull mod = 1e9 + 289;
const int p1 = 1000199, p2 = 1000289;
vector<ull> deg1, deg2;

ull get_hash1(int l, int r, vector<ull> &h) {
    return h[r] - h[l] * deg1[r - l];
}

ull get_hash2(int l, int r, vector<ull> &h) {
    return (h[r] + mod - h[l] * deg2[r - l] % mod) % mod;
}

int main() {
    fast
//  file_in
//  file_in_out

    int n, m;
    cin >> n >> m;
    vector<int> a(2 * n);
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
        a[2 * n - i - 1] = a[i];
    }

    // считаем степени p
    deg1.resize(2 * n + 1); deg2.resize(2 * n + 1);
    deg1[0] = 1; deg2[0] = 1;
    for (int i = 0; i < 2 * n; ++i) {
        deg1[i + 1] = deg1[i] * p1;
        deg2[i + 1] = (deg2[i] * p2) % mod;
    }

    // считаем хеши
    vector<ull> h1(2 * n + 1), h2(2 * n + 1);
    h1[0] = 0; h2[0] = 0;
    for (int i = 0; i < 2 * n; ++i) {
        h1[i + 1] = h1[i] * p1 + a[i];
        h2[i + 1] = (h2[i] * p2 % mod + a[i]) % mod;
    }

    // сравниваем подстроки
    vector<int> ans;
    for (int i = 0; i <= n - i; ++i) {
        if (h1[i] == get_hash1(2 * n - 2 * i, 2 * n - i, h1) && h2[i] == get_hash2(2 * n - 2 * i, 2 * n - i, h2)) {
            ans.push_back(n - i);
        }
    }
    for (int i = (int)ans.size() - 1; i >= 0; --i) {
        cout << ans[i] << " ";
    }
    return 0;
}