#pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define all(a) (a).begin(), (a).end() #define rep(i, n) for (ll i = 0; i < (n); i++) #define req(i, a, b) for (ll i = (a); i < (b); i++) #define pb push_back #define debug(x) cerr << __LINE__ << ' ' << #x << ':' << (x) << '\n' #define debug2(x, y) cerr << __LINE__ << ' ' << #x << ':' << (x) << ',' << #y << ':' << (y) << '\n' #define debug3(x, y, z) cerr << __LINE__ << ' ' << #x << ':' << (x) << ',' << #y << ':' << (y) << ',' << #z << ':' << (z) << '\n' using namespace std; typedef long long ll; typedef unsigned int uint; typedef unsigned long long ull; typedef long double ld; template using P = pair; template using pri_l = priority_queue; template using pri_s = priority_queue, greater>; constexpr int inf = 1000000010; constexpr int inf2 = 2000000010; constexpr ll INF = 1000000000000000010; constexpr ll INF4 = 4000000000000000010; constexpr int mod1e9 = 1000000007; constexpr int mod998 = 998244353; constexpr ld eps = 1e-12; constexpr ld pi = 3.141592653589793238; constexpr ll ten(int n) { return n ? 10 * ten(n - 1) : 1; }; int dx[] = { 1,0,-1,0,1,1,-1,-1,0 }; int dy[] = { 0,1,0,-1,1,-1,1,-1,0 }; ll mul(ll a, ll b) { return (b != 0 && a > INF / b ? INF : a * b); } void fail() { cout << "-1\n"; exit(0); } void no() { cout << "No\n"; exit(0); } template void er(T a) { cout << a << '\n'; exit(0); } template inline bool chmax(T& a, const U& b) { if (a < b) { a = b; return true; } return false; } template inline bool chmin(T& a, const U& b) { if (a > b) { a = b; return true; } return false; } template istream& operator >>(istream& s, vector& v) { for (auto& e : v) s >> e; return s; } template ostream& operator <<(ostream& s, const vector& v) { for (auto& e : v) s << e << ' '; return s; } template ostream& operator << (ostream& s, const pair& p) { s << p.first << ' ' << p.second; return s; } struct fastio { fastio() { cin.tie(0); cout.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(20); cerr << fixed << setprecision(20); } }fastio_; namespace rdv { random_device seed_gen; mt19937_64 engine(seed_gen()); ll rnum(ll r) { return engine() % r; } // [0, r) ll rnum(ll l, ll r) { return rnum(r - l) + l; } // [l, r) ll rng(ll l, ll r) { return rnum(l, r + 1); } // [l, r] double rng01() { return engine() * pow(2, -64); } template void shuf(vector& v) { shuffle(all(v), engine); } void shuf(string& s) { shuffle(all(s), engine); } } using namespace rdv; template vector compress(vector v) { int n = v.size(); vector tmp = v; sort(tmp.begin(), tmp.end()); tmp.erase(unique(tmp.begin(), tmp.end()), tmp.end()); vector res(n); for (int i = 0; i < n; i++) res[i] = lower_bound(tmp.begin(), tmp.end(), v[i]) - tmp.begin(); return res; } #include using namespace atcoder; constexpr ll mod = mod998; using mint = static_modint; istream& operator >>(istream& s, mint& m) { ll y; s >> y; m = y; return s; } ostream& operator <<(ostream& s, mint& m) { return s << m.val(); } ostream& operator <<(ostream& s, const vector& v) { for (auto& e : v) s << e.val() << ' '; return s; } vector fac, inv, facinv; void modcalc(int n) { fac.resize(n); inv.resize(n); facinv.resize(n); fac[0] = 1; fac[1] = 1; inv[1] = 1; facinv[0] = 1; facinv[1] = 1; for (ll i = 2; i < n; i++) { fac[i] = fac[i - 1] * i; inv[i] = -inv[mod % i] * (mod / i); facinv[i] = facinv[i - 1] * inv[i]; } } mint comb(ll n, ll k) { if (n < 0 || k < 0 || n < k) return 0; return fac[n] * facinv[k] * facinv[n - k]; } mint perm(ll n, ll k) { if (n < 0 || k < 0 || n < k) return 0; return fac[n] * facinv[n - k]; } mint hom(ll n, ll k) { if (n < 0 || k < 0 || n == 0 && k > 0) return 0; if (n == 0 && k == 0) return 1; return fac[n + k - 1] * facinv[k] * facinv[n - 1]; } int main() { bool DEBUG = false; // 手数減らないのか~ /*vector> S = { {3,1,0,2},{1,3,2,0},{0,2,3,1},{2,0,1,3} }; map, vector> mp; mp[{0, 1, 2, 3}] = {}; rep(i, 4) mp[S[i]] = { int(i) }; rep(i, 4) { rep(j, 4) { vector p(4); rep(k, 4) p[k] = k; rep(k, 4) p[k] = S[i][p[k]]; rep(k, 4) p[k] = S[j][p[k]]; debug(p); mp[p] = { int(i),int(j) }; } } for (auto [key, val] : mp) { debug2(key, val); }*/ int TEST = 1; cin >> TEST; while (TEST--) { int n; cin >> n; auto f = [&](int i, int j) -> int { return i * n + j + 1; }; vector a(n, vector(n)); rep(i, n) rep(j, n) { if (0 && DEBUG) a[i][j] = i * n + j + 1; else cin >> a[i][j]; } bool bad = false; rep(i, n) rep(j, n) { if (a[i][j] != f(i, j) && a[i][j] != f(i, n - 1 - j) && a[i][j] != f(n - 1 - i, j) && a[i][j] != f(n - 1 - i, n - 1 - j)) bad = true; } if (bad) { cout << "-1\n"; continue; } int last = 2; vector ans; auto op = [&](int type, int v) -> void { assert(type != last); last = type; ans.push_back(v + 1); if (1) { if (type == 1) reverse(all(a[v])); else { rep(i, n / 2) swap(a[i][v], a[n - 1 - i][v]); } } }; // A_i + B_j のパリティが決まっている int t = (n + 1) / 2; vector G(t, vector(t)); rep(i, t) { rep(j, t) { int x = n - 1 - i, y = n - 1 - j; vector vec; vec.push_back(a[i][j]); if (j != y) vec.push_back(a[i][y]); if (i != x) vec.push_back(a[x][j]); if (i != x && j != y) vec.push_back(a[x][y]); int p = 0; int s = ssize(vec); rep(k, s) rep(l, k) if (vec[k] < vec[l]) p ^= 1; G[i][j] = p; } } vector A(t), B(t); rep(i, t) B[i] = G[0][i]; if (n % 2 == 1) B[t - 1] = G[0][t - 1]; for (int i = 1; i < t; i++) A[i] = B[0] ^ G[i][0]; if (n % 2 == 1) A[t - 1] = G[t - 1][0]; rep(i, t) rep(j, t) { if (n % 2 == 1 && i == t - 1 && j == t - 1) { // なんでも OK } else if (n % 2 == 1 && i == t - 1) { if (A[i] != G[i][j]) bad = true; } else if (n % 2 == 1 && j == t - 1) { if (B[j] != G[i][j]) bad = true; } else { if ((A[i] ^ B[j]) != G[i][j]) bad = true; } } if (bad) { cout << "-1\n"; continue; } // debug2(A, B); bool rev = false; vector av, bv; rep(i, t) { if (A[i]) av.push_back(i); if (B[i]) bv.push_back(i); } while (true) { int as = ssize(av), bs = ssize(bv); if (as == bs) break; if (as == bs + 1) { rev = true; break; } if (as > bs) rep(_, 2) bv.push_back(0); if (as < bs) rep(_, 2) av.push_back(0); } // debug2(av, bv); rep(i, ssize(av)) { op(1, av[i]); if (i < ssize(bv)) op(2, bv[i]); } // rep(i, n) rep(j, n) cerr << a[i][j] << " \n"[j == n - 1]; rep(i, t) { rep(j, t) { // 12 手以内 int x = n - 1 - i, y = n - 1 - j; if (i == x or j == y) continue; if (a[i][j] == f(x, y)) { if (!rev) { op(1, x); op(2, j); op(1, x); op(2, j); } else { op(2, y); op(1, i); op(2, y); op(1, i); } } else if (a[i][y] == f(x, y)) { if (!rev) { op(1, i); op(2, y); op(1, i); op(2, y); } else { op(2, y); op(1, x); op(2, y); op(1, x); } } else if (a[x][j] == f(x, y)) { if (!rev) { op(1, x); op(2, y); op(1, x); op(2, y); } else { op(2, j); op(1, x); op(2, j); op(1, x); } } while (a[x][j] != f(x, j)) { if (!rev) { op(1, i); op(2, j); op(1, i); op(2, j); } else { op(2, j); op(1, i); op(2, j); op(1, i); } } if (a[i][j] != f(i, j)) bad = true; } } // rep(i, n) rep(j, n) cerr << a[i][j] << " \n"[j == n - 1]; rep(i, n) rep(j, n) assert(a[i][j] == f(i, j)); // 3N^2 + O(N) 回 int sz = ssize(ans); cout << sz << '\n'; assert(sz <= 4 * n * n); rep(i, sz) cout << ans[i] << " \n"[i == sz - 1]; } }