#include "bits/stdc++.h"
#define ALL(obj) (obj).begin(),(obj).end()
#define RALL(obj) (obj).rbegin(),(obj).rend()
#define REP(i, n) for(int i = 0; i < (int)(n); i++)
#define REPR(i, n) for(int i = (int)(n); i >= 0; i--)
#define FOR(i,n,m) for(int i = (int)(n); i < int(m); i++)
using namespace std;
typedef long long ll;
const int MOD = 1e9 + 7;
const int INF = MOD - 1;
const ll LLINF = 4e18;

void dfs(int i, int j, const vector<vector<int>>& F, vector<vector<bool>>& used) {
    int h = F.size();
    int w = F[0].size();
    if (F[i][j] == 1 && !used[i][j]) {
        used[i][j] = true;
        if (i < h - 1) dfs(i + 1, j, F, used);
        if (j < w - 1) dfs(i, j + 1, F, used);
        if (i > 0) dfs(i - 1, j, F, used);
        if (j > 0) dfs(i, j - 1, F, used);
    }
}

int main() {
    int h, w; cin >> h >> w;
    vector<vector<int>> F(h, vector<int>(w));
    vector<vector<bool>> used(h, vector<bool>(w, false));
    REP(i, h) {
        REP(j, w) {
            cin >> F[i][j];
        }
    }
    int ans = 0;
    REP(i, h) {
        REP(j, w) {
            if (F[i][j] == 1 && !used[i][j]) {
                dfs(i, j,F,used);
                ans++;
            }
        }
    }
    cout << ans << endl;
    getchar(); getchar();
}