#include <bits/stdc++.h>
#include <atcoder/dsu>
using namespace std;
using ll = long long;
#ifdef LOCAL
#include "algo/debug.h"
#else
#define debug(...) (void(0))
#endif
void run_case();
int main() {
	std::ios_base::sync_with_stdio(false);
	std::cin.tie(nullptr);
	int T = 1;
	// cin >> T;
	while (T--) run_case();
	return 0;
}
void run_case() {
	int H, W;
	cin >> H >> W;
	vector<vector<int>> A(H, vector<int>(W));
	for(int i = 0; i < H; i++) for(int j = 0; j < W; j++) cin >> A[i][j];
	atcoder::dsu uf(H * W);
	const int dx[] = {1, 0, -1, 0, -1};
	for(int i = 0; i < H; i++) for(int j = 0; j < W; j++) {
		for(int r = 0; r < 4; r++) {
			int ni = i + dx[r], nj = j + dx[r + 1];
			if(ni < 0 || nj < 0 || ni >= H || nj >= W) continue;
			if(A[ni][nj] == A[i][j]) uf.merge(i * W + j, ni * W + nj);
		}
	}
	int ans = 0;
	for(int i = 0; i < H; i++) for(int j = 0; j < W; j++) if(uf.leader(i * W + j) == i * W + j && A[i][j] == 1) ans++;
	cout << ans << endl;
}