Shared code

#include <bits/stdc++.h>
using namespace std;

vector<int> d = {1, 0, 0, 1, -1, 0, 0, -1};
int n, m;

bool valid(int r, int c, vector<vector<char>> &g) {
    if (r < 0 || c < 0 || r >= n || c >= m || g[r][c] == '#') {
        return false;
    }
    return true;
}

void dfs(int r, int c, vector<vector<char>> &g) {
    g[r][c] = '#';
    for (int i = 0; i < 8; i += 2) {
        if (valid(r + d[i], c + d[i + 1], g)) {
            dfs(r + d[i], c + d[i + 1], g);
        }
    }
}

void bfs(int rs, int cs, vector<vector<char>> &g) {
    queue<vector<int>> q;
    g[rs][cs] = '#';
    q.push({rs, cs});
    while (q.size() > 0) {
        vector<int> cell = q.front();
        q.pop();
        int r = cell[0], c = cell[1];
        for (int i = 0; i < 8; i += 2) {
            if (valid(r + d[i], c + d[i + 1], g)) {
                g[r + d[i]][c + d[i + 1]] = '#';
                q.push({r + d[i], c + d[i + 1]});
            }
        }
    }
}

int main() {
    cin >> n >> m;
    vector<vector<char>> g(n, vector<char> (m));
    
    string str;
    getline(cin, str);
    for (int i = 0; i < n; i++) {
        getline(cin, str);
        for (int j = 0; j < m; j++) {
            g[i][j] = str[j];
        }
    }
    int count;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            if (g[i][j] == '.') {
                bfs(i, j, g);
                count++;
            }
        }
    }
    cout << count;
}