#include using namespace std; static const string CH = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; static mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count()); char rndCh() { return CH[rng() % CH.size()]; } struct Preset { int r, c; vector mat; }; int main() { const int T = 10; const int n = 20, m = 20, k = 20; for (int tc = 1; tc <= T; ++tc) { // 1. Random target vector target(n, string(m, 'A')); for (int i = 0; i < n; ++i) for (int j = 0; j < m; ++j) target[i][j] = rndCh(); // 2. Random presets vector pres(k + 1); for (int p = 1; p <= k; ++p) { int pr = uniform_int_distribution(1, n)(rng); int pc = uniform_int_distribution(1, m)(rng); pres[p].r = pr; pres[p].c = pc; pres[p].mat.assign(pr, string(pc, 'A')); for (int i = 0; i < pr; ++i) for (int j = 0; j < pc; ++j) pres[p].mat[i][j] = rndCh(); } // 3. Generate random operation sequence (forward), apply in reverse // Constraints: total ops <= 4e5, preset <= 400 // For randomness, length can be random between 2e5~4e5 int maxOps = 400000; int wantOps = uniform_int_distribution(200000, 400000)(rng); struct Op { int op, x, y; }; vector ops; ops.reserve(wantOps); int presetUsed = 0; // Start from target and work backwards vector cur = target; auto doBackwardRotate = [&](int x, int y) { // Reverse: undo clockwise rotation, equivalent to counter-clockwise // indices: (x,y), (x,y+1), (x+1,y+1), (x+1,y) // Original clockwise: new = {d, a, b, c} // Reverse: old = {b, c, d, a} char ny = cur[x][y+1]; char nyy = cur[x+1][y+1]; char nyyy= cur[x+1][y]; char nyyyy= cur[x][y]; // Restore old cur[x][y] = ny; cur[x][y+1] = nyy; cur[x+1][y+1] = nyyy; cur[x+1][y] = nyyyy; }; for (int i = 0; i < wantOps; ++i) { // Choose a random operation for variety // 0:-4,1:-3,2:-2,3:-1,4:rotate(0),5:preset int typ = uniform_int_distribution(0, 5)(rng); int op, x, y; if (typ == 5 && presetUsed >= 400) { typ = uniform_int_distribution(0, 4)(rng); } if (typ == 0) { // -4: swap with up if (n <= 1) { --i; continue; } x = uniform_int_distribution(2, n)(rng); y = uniform_int_distribution(1, m)(rng); op = -4; // backward: same swap swap(cur[x-1][y-1], cur[x-2][y-1]); } else if (typ == 1) { // -3: swap with down if (n <= 1) { --i; continue; } x = uniform_int_distribution(1, n-1)(rng); y = uniform_int_distribution(1, m)(rng); op = -3; swap(cur[x-1][y-1], cur[x][y-1]); } else if (typ == 2) { // -2: swap with left if (m <= 1) { --i; continue; } x = uniform_int_distribution(1, n)(rng); y = uniform_int_distribution(2, m)(rng); op = -2; swap(cur[x-1][y-1], cur[x-1][y-2]); } else if (typ == 3) { // -1: swap with right if (m <= 1) { --i; continue; } x = uniform_int_distribution(1, n)(rng); y = uniform_int_distribution(1, m-1)(rng); op = -1; swap(cur[x-1][y-1], cur[x-1][y]); } else if (typ == 4) { // rotate if (n <= 1 || m <= 1) { --i; continue; } x = uniform_int_distribution(1, n-1)(rng); y = uniform_int_distribution(1, m-1)(rng); op = 0; // backward rotate doBackwardRotate(x-1, y-1); } else { // preset int pid = uniform_int_distribution(1, k)(rng); int pr = pres[pid].r; int pc = pres[pid].c; x = uniform_int_distribution(1, n - pr + 1)(rng); y = uniform_int_distribution(1, m - pc + 1)(rng); op = pid; presetUsed++; // backward: fill this region with random chars for (int ii = 0; ii < pr; ++ii) for (int jj = 0; jj < pc; ++jj) cur[x - 1 + ii][y - 1 + jj] = rndCh(); } ops.push_back({op, x, y}); } // Now cur is the initial state vector initial = cur; // 4. Write to file { string fname = to_string(tc) + ".in"; ofstream fout(fname); fout << n << " " << m << " " << k << "\n"; for (int i = 0; i < n; ++i) fout << initial[i] << "\n"; fout << "\n"; for (int i = 0; i < n; ++i) fout << target[i] << "\n"; for (int p = 1; p <= k; ++p) { fout << "\n"; fout << pres[p].r << " " << pres[p].c << "\n"; for (int i = 0; i < pres[p].r; ++i) fout << pres[p].mat[i] << "\n"; } fout.close(); } // 5. Output empty ans file { string fname = to_string(tc) + ".ans"; ofstream fout(fname); // empty fout.close(); } cerr << "generated " << tc << ".in/.out, ops=" << ops.size() << ", presetsUsed=" << presetUsed << "\n"; } return 0; }