突发奇想

这题是不是也能用并查集做？

#include<bits/stdc++.h>
using namespace std;
int n, m, f[10005];
vector<string> v(1);
int id(int i, int j){
    return (i - 1) * m + j;
}int find(int x){
    return f[x] == x? x: f[x] = find(f[x]);
}void uni(int x, int y){
    f[find(x)] = find(y);
}signed main(){
    scanf("%d%d", &n, &m);
    iota(f, f + n * m + 1, 0);
    for(int i = 1; i <= n; ++i){
        string s;
        cin >> s;
        v.push_back(string(1, ' ') + s);
    }for(int i = 1; i <= n; ++i){
        for(int j = 1; j <= m; ++j){
            if(v[i][j] == '#')
                continue;
            if(i != n and v[i + 1][j] == '.')
                uni(id(i, j), id(i + 1, j));
            if(j != m and v[i][j + 1] == '.')
                uni(id(i, j), id(i, j + 1));
            if(i != 1 and v[i - 1][j] == '.')
                uni(id(i, j), id(i - 1, j));
            if(j != 1 and v[i][j - 1] == '.')
                uni(id(i, j), id(i, j - 1));
        }
    }printf("%s", find(1) == find(n * m)? "Yes": "No");
    return 0;
}