AOJ 1160:島はいくつある？

vector<vector<int>> g_graph;
vector<vector<int>> g_visited;
int dy[] = {-1, -1, -1, 0, 0, 1, 1, 1};
int dx[] = {-1, 0, 1, -1, 1, -1, 0, 1};

void dfs(int y, int x, int h, int w) {
    g_visited[y][x] = true;
    for (int i = 0; i < 8; i++) {
        int ny = y + dy[i], nx = x + dx[i];
        if (ny < 0 || ny >= h || nx < 0 || nx >= w) {
            continue;
        }
        if (g_visited[ny][nx]) {
            continue;
        }
        if (g_graph[ny][nx] == 0) {
            continue;
        }
        dfs(ny, nx, h, w);
    }
}

void go(int y, int x, int h, int w, int &island) {
    if (g_visited[y][x]) {
        return;
    }
    if (g_graph[y][x] == 0) {
        return;
    }
    dfs(y, x, h, w);
    island += 1;
}

void solve(int h, int w) {
    g_graph.assign(h, vector<int>(w, 0));
    g_visited.assign(h, vector<int>(w, 0));
    for (int i = 0; i < h; i++) {
        for (int j = 0; j < w; j++) {
            cin >> g_graph[i][j];
        }
    }

    int island = 0;
    for (int i = 0; i < h; i++) {
        for (int j = 0; j < w; j++) {
            go(i, j, h, w, island);
        }
    }
    cout << island << endl;
}

signed main() {
    while (1) {
        int w, h;
        cin >> w >> h;
        if (w == 0 && h == 0) {
            return 0;
        } else {
            solve(h, w);
        }
    }
}