Sokkelo

input/code.cpp: In function 'int main()':
input/code.cpp:51:14: warning: 'bx' may be used uninitialized in this function [-Wmaybe-uninitialized]
  if (o[by][bx]) {
      ~~~~~~~~^
input/code.cpp:51:14: warning: 'by' may be used uninitialized in this function [-Wmaybe-uninitialized]

#include <iostream>
#include <vector>
#include <queue>
#include <tuple>

using namespace std;
using ll = long long;

int n, m;
pair<int, int> ds[4] = {{-1, 0}, {0, -1}, {0, 1}, {1, 0}};
bool t[1001][1001];
int o[1001][1001];
vector<pair<int, int>> s[3];
int d[1001][1001];
bool z[1001][1001];

void dfs(int y, int x, int v)
{
	if (y < 0 || n <= y || x < 0 || m <= x) return;
	if (t[y][x]) return;
	if (o[y][x]) return;
	o[y][x] = v;
	s[v].emplace_back(y, x);
	for (auto [dy, dx] : ds) {
		dfs(y+dy, x+dx, v);
	}
}

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cin >> n >> m;
	int ay, ax, by, bx;
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < m; ++j) {
			char c;
			cin >> c;
			t[i][j] = c == '#';
			if (c == 'A') {
				ay = i;
				ax = j;
			}
			if (c == 'B') {
				by = i;
				bx = j;
			}
		}
	}
	dfs(ay, ax, 1);
	if (o[by][bx]) {
		cout << 1 << endl;
		return 0;
	}
	dfs(by, bx, 2);
	int mi = 1e9;
	priority_queue<tuple<int, int, int>> q;
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < m; ++j) {
			d[i][j] = 1e9;
		}
	}
	d[ay][ax] = 0;
	q.emplace(0, ay, ax);
	while (!q.empty()) {
		auto [c, y, x] = q.top();
		q.pop();
		c = -c;
		if (z[y][x]) continue;
		z[y][x] = 1;
		for (auto [dy, dx] : ds) {
			int ny = y+dy, nx = x+dx;
			if (ny < 0 || n <= ny || nx < 0 || m <= nx) continue;
			if (d[y][x] + (o[ny][nx] != 1) < d[ny][nx]) {
				d[ny][nx] = d[y][x] + (o[ny][nx] != 1);
				if (o[ny][nx] == 2) {
					mi = min(mi, d[ny][nx]);
				} else {
					q.emplace(-d[ny][nx], ny, nx);
				}
			}
		}
	}
	cout << mi << endl;
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 2

Verdict: ACCEPTED

Test 5

Group: 2

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 1, 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 1, 2

Verdict: ACCEPTED

Test 11

Group: 2

Verdict: ACCEPTED

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