#include <iostream>
#include <fstream>

using namespace std;

ifstream fin("fill.in");
ofstream fout("fill.out");

int A[1001][1001], n, m;

const int di[] = {0, 0, -1, 1},
      dj[] = {-1, 1, 0, 0};

void Fill(int i, int j, int val)
{
    if(i <= n && j <= m && i >= 1 && j >= 1 && A[i][j] ==  1)
    {
        A[i][j] = val;
        for(int k = 0; k < 4; k++)
            Fill(i + di[k], j + dj[k], val);
    }
}

int main()
{
    fin >> n >> m;
    for(int i = 1; i <= n; i++)
        for(int j = 1; j <= m; j++)
            fin >> A[i][j];

    int cnt = 0;

    for(int i = 1; i <= n; i++)
        for(int j = 1; j <= m; j++)
            if(A[i][j] == 1)
        {
            cnt++;
            Fill(i, j, 2);
        }
    fout << cnt;

    return 0;
}