#define _CRT_SECURE_NO_DEPRECATE
#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <algorithm>
#include <cmath>
#include <map>
#include <set>
#include <ctime>
#include <sstream>
#include <numeric>

#define sz(x) (int)(x).size()
#define all(x) (x).begin(),(x).end()
#define EPS 1e-9
#define INF INT_MAX
#define SQR(X) (X) * (X)
#define round(x) (int)floor((x) + 0.5 + EPS)

using namespace std;

typedef pair <int, int> pii;
typedef vector <int> vi;
typedef vector <vi> vvi;
typedef vector <pii> vpii;
typedef vector <vpii> vvpii;
typedef vector <string> vs;
typedef unsigned int uint;

const int N = 100;
int a[N][N] = {0};
int n, m;
int dx[] = {0, 0, 1, -1};
int dy[]  = {1, -1, 0, 0};


void DFS(int y, int x)
{
    a[y][x] = 1;
    for (int i = 0; i < 4; i++)
    {
        int nx = x;
        int ny = y;
        nx += dx[i];
        ny += dy[i];
        if (nx < 0 || nx > m - 1) continue;
        if (ny < 0 || ny > n - 1) continue;
        if (a[ny][nx]) continue;
        DFS(ny, nx);
    }
}

int main()
{
#ifndef ONLINE_JUDGE
    freopen("d.in", "r", stdin);
    freopen("d.out", "w", stdout);
#endif
    scanf("%d%d", &n, &m);
    for (int i = 0; i < n; i++)
        for (int j = 0; j < m; j++)
            scanf("%d", &a[i][j]);
    int res = 0;
    for (int i = 0; i < n; i++)
        for (int j = 0; j < m; j++)
        {
            if (a[i][j]) continue;
            DFS(i, j);
            res++;
        }
    printf("%d", res);
    return 0;
}