#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;

struct UnionFind {
    vector<int> data;
    int __size;
    UnionFind(int size) : data(size, -1), __size(size) { }
    bool unionSet(int x, int y) {
        if ((x = root(x)) != (y = root(y))) {
            if (data[y] < data[x]) swap(x, y);
            data[x] += data[y]; data[y] = x; __size--;
        }
        return x != y;
    }
    bool findSet(int x, int y) { return root(x) == root(y); }
    int root(int x) { return data[x] < 0 ? x : data[x] = root(data[x]); }
    int size(int x) { return -data[root(x)]; }
    int size() { return __size; }
};

int main() {
    const int ALIVE = 1;
    int h, w; cin >> h >> w;
    vector<vector<int>> field(h, vector<int>(w));
    for (auto &row: field) for (auto &c: row) cin >> c;
    auto idx = [&](int i, int j) { return i * w + j; };
    auto out_field = [&](int i, int j) { return i < 0 || i >= h || j < 0 || j >= w; };
    UnionFind uf(h * w);
    int cnt = 0;
    for (int i = 0; i < h; i++) for (int j = 0; j < w; j++) {
        if (field[i][j] != ALIVE) continue;
        cnt++;
        for (int di: {-1, 0, 1}) for (int dj: {-1, 0, 1}) {
            if (di * di + dj * dj != 1) continue;
            int ni = i + di, nj = j + dj;
            if (out_field(ni, nj) || field[ni][nj] != ALIVE) continue;
            if (idx(i, j) < idx(ni, nj)) uf.unionSet(idx(i, j), idx(ni, nj));
        }
    }
    int cnt_wall = h * w - cnt;
    cout << uf.size() - cnt_wall << endl;
    return 0;
}