比赛 2025暑期集训第7场 评测结果 W
题目名称 天气预报 最终得分 0
用户昵称 LikableP 运行时间 0.007 s
代码语言 C++ 内存使用 1.72 MiB
提交时间 2025-08-11 17:24:46
显示代码纯文本
#include <cstdio>

int n;
int target[366][110];
int dx[] = {0, -1, 0, 1, 0, -2, 0, 2, 0};
int dy[] = {0, 0, 1, 0, -1, 0, 2, 0, -2};

bool f(int x, int y) {
  return 3 * (x - 1) + y;
}

bool check(__int128 x) {
  for (int i = 1; i <= 16; ++i) {
    if ((x >> i * 3 & 7) == 7) return false;
  }
  return true;
}

void write(__int128 x) {
  printf("<write>\n");
  for (int i = 127; i >= 0; --i) {
    putchar((x >> i & 1) ^ 48);
  }
  putchar('\n');
}

__int128 anc(__int128 status, int x, int y) {
  __int128 add = 0;
  for (int i = 1; i <= 16; ++i) {
    if (i == f(x, y) || i == f(x, y + 1) || i == f(x + 1, y) || i == f(x + 1, y + 1)) continue;
    add |= 1 << (i * 3);
  }
  return status + add;
}

__int128 dec(__int128 status, int x, int y) {
  __int128 minus = 0;
  for (int i = 1; i <= 16; ++i) {
    if (status >> i * 3 & 7) {
      minus |= 1 << i * 3;
    }
  }
  return status - minus;
}

bool dfs(int day, int x, int y, __int128 status) {
  if (day > n) {
    return true;
  }

  if (target[day][f(x, y)] == 1 || target[day][f(x + 1, y)] || target[day][f(x, y + 1)] || target[day][f(x + 1, y + 1)]) return false;
  if (!check(status)) return false;
  __int128 sta = dec(status, x, y);

  for (int i = 1; i <= 8; ++i) {
    int cx = x + dx[i], cy = y + dy[i];
    if (cx < 1 || cx > 3 || cy < 1 || cy > 3) continue;
    if (dfs(day + 1, cx, cy, anc(sta, x, y))) return true;
  }

  return false;
}

int main() {
  freopen("weather_forecast.in", "r", stdin);
  freopen("weather_forecast.out", "w", stdout);
  while (scanf("%d", &n)) {
    if (!n) break;
    for (int i = 1; i <= n; ++i) {
      for (int j = 1; j <= 16; ++j) {
        scanf("%d", &target[i][j]);
      }
    }

    if (dfs(1, 2, 2, 0)) {
      puts("1");
    } else {
      puts("0");
    }
  }
  return 0;
}