Sokkelo

#include <bits/stdc++.h>

using namespace std;

const int N = 1002;
const int inf = 1e9;

int n,m;
int r = inf;
int v[N][N];

void f(int x, int y)
{
    if(v[x][y] != 1) return;
    v[x][y] = 2;
    f(x+1, y);
    f(x, y+1);
    f(x-1, y);
    f(x, y-1);
}

void fr(int x, int y)
{
    queue<pair<pair<int,int>,int>> q;
    q.push({{x,y},0});
    while(!q.empty())
    {
        auto e = q.front(); q.pop();
        int x = e.first.first;
        int y = e.first.second;
        int dist = e.second;
        if(x<=0 || y<=0 || x>n || y>m) continue;
        if(dist > 0 || v[x][y] == 0)
        {
            dist++;
            if(v[x][y] == 0)
            {
                v[x][y] = 3;
                q.push({{x+1, y}, dist});
                q.push({{x, y+1}, dist});
                q.push({{x-1, y}, dist});
                q.push({{x, y-1}, dist});
            }
            else if(v[x][y] == 2)
            {
                r = min(r, dist);
            }
        }
        else if(v[x][y] == 1)
        {
            v[x][y] = 3;
            q.push({{x+1, y}, 0});
            q.push({{x, y+1}, 0});
            q.push({{x-1, y}, 0});
            q.push({{x, y-1}, 0});
        }
    }
}

int main()
{
    cin>>n>>m;
    char c;
    pair<int,int> kv;
    pair<int,int> jt;
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=m;j++)
        {
            cin>>c;
            v[i][j] = (c != '#' ? 1 : 0);
            if(c == 'A') kv = {i,j};
            if(c == 'B') jt = {i,j};
        }
    }
    f(kv.first, kv.second);
    fr(jt.first, jt.second);
    if(r == inf) r = 1;
    cout<<r;
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: WRONG ANSWER

Test 4

Group: 2

Verdict: ACCEPTED

Test 5

Group: 2

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: WRONG ANSWER

Test 7

Group: 1, 2

Verdict: WRONG ANSWER

Test 8

Group: 2

Verdict: WRONG ANSWER

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 1, 2

Verdict: WRONG ANSWER

Test 11

Group: 2

Verdict: WRONG ANSWER

Test 12

Group: 1, 2

Verdict: ACCEPTED

Test 13

Group: 2

Verdict: ACCEPTED

Test 14

Group: 1, 2

Verdict: ACCEPTED

Test 15

Group: 2

Verdict: ACCEPTED

Test 16

Group: 2

Verdict: ACCEPTED

Test 17

Group: 2

Verdict: ACCEPTED