[AcWing 1098] 城堡问题

#include<bits/stdc++.h>

using namespace std;

typedef long long LL;

const int N = 1000 + 10;

#define x first
#define y second

int n, m;
int g[N][N];
bool st[N][N];
int dx[] = {0, -1, 0, 1};
int dy[] = {-1, 0, 1, 0};

int bfs(int x, int y)
{
    queue<pair<int,int>> q;
    q.push({x, y});
    st[x][y] = true;
    int cnt = 0;
    while (q.size()) {
        auto t = q.front();
        q.pop();
        cnt ++;
        for (int i = 0; i < 4; i ++) {
            if (g[t.x][t.y] >> i & 1)
                continue;
            int a = t.x + dx[i], b = t.y + dy[i];
            if (a < 1 || a > n || b < 1 || b > m || st[a][b])
                continue;
            q.push({a, b});
            st[a][b] = true;
        }
    }
    return cnt;
}

void solve()
{
    cin >> n >> m;
    for (int i = 1; i <= n; i ++)
        for (int j = 1; j <= m; j ++)
            cin >> g[i][j];
    int res = 0, cnt = 0;
    for (int i = 1; i <= n; i ++)
        for (int j = 1; j <= m; j ++)
            if (!st[i][j]) {
                res = max(res, bfs(i, j));
                cnt ++;
            }
    cout << cnt << endl;
    cout << res << endl;
}

signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    solve();

    return 0;
}