#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <cstring>
#include <queue>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <map>
#include <functional>
#include <cmath>
#include <cassert>
#include <string>
#include <iostream>

using namespace std;
typedef long long ll;
typedef pair<int, int> P;
//typedef pair<ll, ll> P;
ll MOD = 1000000007;
//ll INF = 1LL << 60;

template <typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val)
{
   fill((T *)array, (T *)(array + N), val);
}
int a[3010][3010];
int main()
{
   ios::sync_with_stdio(false);
   cin.tie(0);

   int h, w;
   cin >> h >> w;
   int ans = 0;
   queue<P> one;
   for (ll i = 0; i < h; i++)
   {
      for (ll j = 0; j < w; j++)
      {
         cin >> a[i][j];
         if (a[i][j] == 1)
         {
            one.push(P(j, i));
            ans = 1;
         }
      }
   }
   if(one.empty()){
      cout << 0 << endl;
      return 0;
   }

   queue<P> q;
   q.push(P(one.front().first , one.front().second));
   
   one.pop();
   int xl[] = {0, 1, 0, -1};
   int yl[] = {-1, 0, 1, 0};
   while (!one.empty())
   {
      if (q.empty())
      {
         while(true){
            P pp = P(one.front().first, one.front().second);
            one.pop();
            if(a[pp.second][pp.first]==1){               
               q.push(pp);
               ans++;
               break;
            }else{
               if(one.empty()){
                  cout << ans << endl;
                  return 0;
               }
               continue;
            }
         }
      }
      int x = q.front().first;
      int y = q.front().second;
      q.pop();
      a[y][x] = 0;

      for (int i = 0; i < 4; i++)
      {
         int nx = x + xl[i];
         int ny = y + yl[i];
         if (nx < 0 || ny < 0 || nx >= w || ny >= h || a[ny][nx] == 0)
            continue;
         q.push(P(nx, ny));
         a[ny][nx] = 0;
      }

   }

   cout << ans << endl;
}