#include <stdio.h>
#include <stdlib.h>


int n, m;
char c[502][502];
short int seen[250001];
unsigned long int szint[250001], apa[250001], graf[250001][5];
unsigned long int l = 0;

void Init()
{
    int i, j;

    for (i = 1; i <= n*m; i++)
    {
        seen[i] = 0;
        for (j = 0; j < 5; j++)
            graf[i][j] = 0;
    }

    for (i = 1; i <= n+1; i++)
        for (j = 1; j <= m+1; j++)
            c[i][j] = '0';
}

int ElvagoEl(unsigned long int v, unsigned long int sz)
{
    unsigned long int rfminvm = 1000000, i, uminvm;

    seen[v] = 1;
    szint[v] = sz;

    for (i = 1; i <= graf[v][0]; i++)
    {
        if ((graf[v][i]) && (!seen[graf[v][i]]))
        {
            apa[graf[v][i]] = v;
            uminvm = ElvagoEl(graf[v][i], sz+1);
            if (uminvm <= sz)
                if (uminvm < rfminvm)
                    rfminvm = uminvm;
        }
        else if ((graf[v][i]) && (seen[i] == 1))
        {
            if (szint[graf[v][i]] < sz-1)
                if (szint[graf[v][i]] < rfminvm)
                    rfminvm = szint[graf[v][i]];
        }
    }
    seen[v] = 2;
    if (rfminvm != 1000000)
            l++;
    return rfminvm;
}


int main()
{
    int i, j;
    unsigned long int k;

    scanf("%d%d", &n, &m);

    Init();
    gets(c[0]);
    for (i = 0; i < n; i++)
        for (j = 0; j < m+1; j++)
            scanf("%c", &c[i][j]);

    for (i = 0; i < n; i++)
        for (j = 0; j < m; j++)
            if (c[i][j] == '1')
            {
                if (c[i+1][j] == '1')
                {
                    graf[i*m+j+1][0]++;
                    graf[i*m+j+1][graf[i*m+j+1][0]] = (i+1)*m+j+1;
                    graf[(i+1)*m+j+1][0]++;
                    graf[(i+1)*m+j+1][graf[(i+1)*m+j+1][0]] = i*m+j+1;
                }
                if (c[i][j+1] == '1')
                {
                    graf[i*m+j+1][0]++;
                    graf[i*m+j+1][graf[i*m+j+1][0]] = i*m+j+2;
                    graf[i*m+j+2][0]++;
                    graf[i*m+j+2][graf[i*m+j+2][0]] = i*m+j+1;
                }
            }

    for (i = 0; i < n; i++)
        for (j = 0; j < m; j++)
            if (!seen[i*m+j+1])
                k = ElvagoEl(i*m+j+1, 0);

    printf("%lu", l);
    return 0;
}