#include<bits/stdc++.h>
using namespace std;
int dx[4] = {-1, 1, 0, 0};
int dy[4] = {0, 0, -1, 1};
int n, m;
vector<string> grid;
void dfs(int x, int y) {
    grid[x][y] = '0';
    for (int i = 0; i < 4; ++i) {
        int nx = x + dx[i], ny = y + dy[i];
        if (nx >= 0 && nx < n && ny >= 0 && ny < m && grid[nx][ny] != '0') {
            dfs(nx, ny);
        }
    }
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cin >> n >> m;
    grid.resize(n);
    for (int i = 0; i < n; ++i) cin >> grid[i];
    int cellCount = 0;
    for (int i = 0; i < n; ++i)
        for (int j = 0; j < m; ++j)
            if (grid[i][j] != '0') {
                cellCount++;
                dfs(i, j);
            }
    cout << cellCount << endl;
    return 0;
}