#include <iostream>
#include <vector>
using namespace std;
int H,W;
int ans=0;
bool not1(vector<vector<int>> A)
{
	int i,j;
	for (i=1;i<=H;i++){
		for (j=1;j<=W;j++){
			if (A[i][j]==1){
				return false;
			}
		}
	}
	return true;
}
void check(vector<vector<int>> &A,int I,int J,int &index)
{
	if (A[I][J]==1){
		ans++;
		index++;
		A[I][J]=index;
		if (A[I-1][J]==1){
			A[I-1][J]=index;
		}
		if (A[I+1][J]==1){
			A[I+1][J]=index;
		}
		if (A[I][J-1]==1){
			A[I][J-1]=index;
		}
		if (A[I][J+1]==1){
			A[I][J+1]=index;
		}
		int i,j;
		for (i=I;i<=H;i++){
			for (j=J+1;j<=W;j++){
				if (A[i][j]==0 ){
					continue;
				}
				if (A[i-1][j]==index || A[i+1][j]==index || A[i][j-1]==index || A[i][j+1]==index){
					A[i][j]=index;
					if (A[i-1][j]==1){
						A[i-1][j]=index;
					}
					if (A[i+1][j]==1){
						A[i+1][j]=index;
					}
					if (A[i][j-1]==1){
						A[i][j-1]=index;
					}
					if (A[i][j+1]==1){
						A[i][j+1]=index;
					}
				}
			}
		}
	}	
}
int main(int argc, char* argv[])
{
	cin>>H>>W;
	int n0=0,n1=0;
	vector<vector<int>> A(H+2,vector<int>(W+2));
	int i,j;
	for (i=1;i<=H;i++){
		for (j=1;j<=W;j++){
			cin>>A[i][j];
			if (A[i][j]==0){
				n0++;
			}else{
				n1++;
			}
		}
	}
	if (n0==H*W){
		cout<<0<<endl;
		return 0;
	}
	if (n1==H*W){
		cout<<1<<endl;
		return 0;
	}
	int index=1;
	for (i=1;i<=H;i++){
		for (j=1;j<=W;j++){
			check(A,i,j,index);
		}
	}
	cout<<ans<<endl;
	return 0;
}