871.cpp

#include <bits/stdc++.h>
using namespace std;
int dx[] = {-1, 0, 0, 1, -1, -1, 1, 1};
int dy[] = {0, -1, 1, 0, -1, 1, -1, 1};
char a[50][50];
int N, M;
int call(int i, int j) {
    int sum = 0;
    if (i < 0 || j < 0 || i >= N || j >= M) return 0;
    if (a[i][j] == '0') return 0;
    sum = 1;
    a[i][j] = '0';
    for (int k = 0; k < 8; k++) {
        sum += call(i + dx[k], j + dy[k]);
    }
    return sum;
}

int main() {
    int n, m, i, j, k, tc, t = 1;
    cin >> tc;
    getchar();
    getchar();
    while (tc--) {
        N = n;
        M = m;
        i = 0;
        while (gets(a[i])) {
            if (strlen(a[i]) == 0) break;
            i++;
        }
        N = i;
        M = strlen(a[0]);
        int mx = 0;
        for (i = 0; i < N; i++) {
            for (j = 0; j < M; j++) {
                if (a[i][j] == '1') {
                    k = call(i, j);
                    if (k > mx) mx = k;
                }
            }
        }
        if (t != 1) puts("");
        t++;
        printf("%d\n", mx);
    }
    return 0;
}