Submission #990434

#	Time	Username	Problem	Language	Result	Execution time	Memory
990434		tch1cherin	Red-blue table (IZhO19_stones)	C++17	0 / 100	17 ms	1372 KiB

stones

#include <bits/stdc++.h>
using namespace std;
 
int main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  int T;
  cin >> T;
  while (T--) {
    int N, M;
    cin >> N >> M;
    int H = N - 2 + N % 2, W = M - 2 + M % 2;
    if (N == 4 && M == 4) {
      cout << "5\n+++-\n+++-\n+++-\n+++-\n"; 
    } else if (H + W < max(N, M) + (min(N, M) + 1) / 2) {
      if (N > M) {
        if (M <= 2) {
          cout << N << "\n";
          for (int i = 0; i < N; i++) {
            cout << string(M, '+') << "\n";
          }
        } else if (M <= 4) {
          cout << N + 1 << "\n";
          for (int i = 0; i < N; i++) {
            cout << string(M - 1, '+') << "-\n";
          }
        } else {
          cout << N + (M + 1) / 2 << "\n";
          vector<string> s(N, string(M, 0));
          for (int i = 0; i < N; i++) {
            for (int j = 0; j < M / 2; j++) {
              s[i][j] = '+';
            }
            for (int j = M / 2; j < M; j++) {
              s[i][j] = (j - M / 2) % ((M + 1) / 2) == i % ((M + 1) / 2) ? '+' : '-';
            }
          }
          for (int i = 0; i < N; i++) {
            cout << s[i] << "\n";
          }
        }
      } else {
        if (N <= 2) {
          cout << M << "\n";
          for (int i = 0; i < N; i++) {
            cout << string(M, '-') << "\n";
          }
        } else if (N <= 4) {
          cout << M + 1 << "\n";
          for (int i = 0; i < N; i++) {
            cout << (i < N - 1 ? string(M, '+') : string(M, '-')) << "\n";
          }
        } else {
          cout << (N + 1) / 2 + M << "\n";
          vector<string> s(N, string(M, 0));
          for (int j = 0; j < M; j++) {
            for (int i = 0; i < N / 2; i++) {
              s[i][j] = '-';
            }
            for (int i = N / 2; i < N; i++) {
              s[i][j] = (i - N / 2) % ((N + 1) / 2) == j % ((N + 1) / 2) ? '-' : '+';
            }
          }
          for (int i = 0; i < N; i++) {
            cout << s[i] << "\n";
          }
        }
      }
    } else {
      cout << H + W << "\n";
      for (int i = 0; i < N; i++) {
        for (int j = 0; j < M; j++) {
          if (i < H && j < W) {
            cout << "+-"[(i + j) % 2];
          } else if (i < H) {
            cout << "+";
          } else {
            cout << "-";
          }
        }
        cout << "\n";
      }
    }
  }
}

• Subtask 1: 0 / 17
• Subtask 2: 0 / 10
• Subtask 3: 0 / 16
• Subtask 4: 0 / 11
• Subtask 5: 0 / 15
• Subtask 6: 0 / 31