/* -*- coding: utf-8 -*-
 *
 * 697.cc: No.697 池の数はいくつか - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_H = 3000;
const int MAX_W = 3000;

const int dxs[] = { 1, 0, -1, 0 }, dys[] = { 0, -1, 0, 1 };

/* typedef */

typedef pair<int,int> pii;

/* global variables */

bool flds[MAX_H][MAX_W], used[MAX_H][MAX_W];

/* subroutines */

/* main */

int main() {
  int h, w;
  scanf("%d%d", &h, &w);

  for (int y = 0; y < h; y++)
    for (int x = 0; x < w; x++) {
      int a;
      scanf("%d", &a);
      flds[y][x] = (a > 0);
    }

  int cnt = 0;
  for (int y = 0; y < h; y++)
    for (int x = 0; x < w; x++)
      if (flds[y][x] && ! used[y][x]) {
	cnt++;
	used[y][x] = true;
	queue<pii> q;
	q.push(pii(x, y));

	while (! q.empty()) {
	  pii u = q.front(); q.pop();
	  int &ux = u.first, &uy = u.second;

	  for (int di = 0; di < 4; di++) {
	    int vx = ux + dxs[di], vy = uy + dys[di];
	    if (vx >= 0 && vx < w && vy >= 0 && vy < h &&
		flds[vy][vx] && ! used[vy][vx]) {
	      used[vy][vx] = true;
	      q.push(pii(vx, vy));
	    }
	  }
	}
      }

  printf("%d\n", cnt);
  return 0;
}