1371A. Magical Sticks

  1. int main() {
  2.     cin.tie(nullptr)->sync_with_stdio(false);
  3.     int _; for (cin >> _; _--;) {
  4.         ll n; cin >> n;
  5.         cout << (n + 1) / 2 << "\n";
  6.     }
  7. }

1371B. Magical Calendar

  1. int main() {
  2.     cin.tie(nullptr)->sync_with_stdio(false);
  3.     int _; for (cin >> _; _--;) {
  4.         ll n, r;
  5.         cin >> n >> r;
  6.         ll k = min(n - 1, r);
  7.         cout << (k + 1) * k / 2 + (r >= n) << "\n";
  8.     }
  9. }

1371C. A Cookie for You

  1. void solve() {
  2.     ll a, b, n, m;
  3.     cin >> a >> b >> n >> m;
  4.     cout << (a + b >= n + m and min(a, b) >= m ? "YES\n" : "NO\n");
  5. }

1371D. Grid-00100

  1. const int maxn = 300;
  2. int A[maxn][maxn];
  3. void solve() {
  4.     ll n, k;
  5.     cin >> n >> k;
  6.     cout << not not(k % n) * 2 << "\n";
  7.     for (int i = 0; i < n; i += 1)
  8.         for (int j = 0; j < n; j += 1) A[i][j] = 0;
  9.     for (int i = 0; i < n; i += 1)
  10.         for (int j = 0; j < n; j += 1)
  11.             if (k) {
  12.                 A[j][(i + j) % n] = 1;
  13.                 k -= 1;
  14.             }
  15.     for (int i = 0; i < n; i += 1) {
  16.         for (int j = 0; j < n; j += 1) cout << A[i][j];
  17.         cout << "\n";
  18.     }
  19. }