Shared code

#include <bits/stdc++.h>
#define uwu return 0;
using namespace std;

#define fs first
#define sc second

const int SIZE = 1e3 + 5, dx[4] = {1, 0, -1, 0}, dy[4] = {0, -1, 0, 1};

int n, m;

char cmap[SIZE][SIZE];

bool bmap[SIZE][SIZE];

bool able(int x,int y){
    return (x > -1 && y > -1 && x < n && y < m && cmap[x][y] == '.' && (!bmap[x][y]));
}

void BFS(int x,int y){
    queue<pair<int, int>> BFS;
    BFS.push({x, y});
    while(!BFS.empty()){
        pair<int, int> temp = BFS.front();
        BFS.pop();
        for (int i = 0; i < 4;i++){
            if(able(temp.fs + dx[i], temp.sc + dy[i])){
                bmap[temp.fs + dx[i]][temp.sc + dy[i]] = 1;
                BFS.push({temp.fs + dx[i], temp.sc + dy[i]});
            }
        }
    }
    return;
}

int main(){
    cin >> n >> m;
    for (int i = 0; i < n;i++){
        for (int j = 0; j < m;j++){
            cin >> cmap[i][j];
        }
    }

    int answer = 0;
    
    for (int i = 0; i < n;i++){
        for (int j = 0; j < m;j++){
            if(able(i,j)){
                BFS(i, j);
                answer++;
            }
        }
    }
    cout << answer << '\n';
    uwu
}