E-Bishop-2, 01 BFS

// https://atcoder.jp/contests/abc246/tasks/abc246_e
// 0-1 BFS
#include <bits/stdc++.h>
// #include <atcoder/all>
using namespace std;
#define int long long
#define all(x) (x).begin(), (x).end()
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pair<int, int>> vpi;
typedef pair<int, int> pi;
typedef pair<pi, int> ppi;
#define f first
#define s second
#define pb push_back
#define endl "\n"
#define yes cout << "YES" << endl
#define no cout << "NO" << endl
int dx[] = {-1, 1, -1, 1};
int dy[] = {-1, 1, 1, -1};
const int mod1 = 1e9 + 7, mod2 = 998244353, INF = 2e18, N = 2e5 + 5, L = 19;
int gcd(int a, int b) { return b == 0 ? a : gcd(b, a % b); }
// -----------------------------------------------------------------------------
void solve()
{
    int n, ax, ay, bx, by;
    cin >> n >> ax >> ay >> bx >> by;
    ax--, ay--, bx--, by--;
    vector<string> grid(n);
    for (int i = 0; i < n; i++)
    {
        cin >> grid[i];
    }
    auto inside = [&](int nx, int ny) -> bool
    {
        return (nx >= 0 && nx < n && ny >= 0 && ny < n && grid[nx][ny] != '#');
    };
    // x, y, direction -> unique state
    vector<vvi> dis(n, vvi(n, vi(4, INF)));
    vector<vvi> vis(n, vvi(n, vi(4, 0)));
    deque<ppi> dq;
    for (int i = 0; i < 4; i++)
    {
        int nx = ax + dx[i];
        int ny = ay + dy[i];
        if (inside(nx, ny))
        {
            if (dis[nx][ny][i] > 1)
            {
                dis[nx][ny][i] = 1;
                dq.push_back({{nx, ny}, i});
            }
        }
    }
    while (!dq.empty())
    {
        auto cur = dq.front();
        dq.pop_front();
        int x = cur.f.f;
        int y = cur.f.s;
        int d = cur.s;
        if (x == bx && y == by)
        {
            cout << dis[x][y][d] << endl;
            return;
        }
        if (vis[x][y][d])
        {
            continue;
        }
        vis[x][y][d] = 1;
        int curd = dis[x][y][d];
        for (int i = 0; i < 4; i++)
        {
            int nx = x + dx[i];
            int ny = y + dy[i];
            if (!inside(nx, ny))
            {
                continue;
            }
            int newd = curd + (i == d ? 0 : 1);
            if (dis[nx][ny][i] > newd)
            {
                dis[nx][ny][i] = newd;
                if (i == d)
                {
                    dq.push_front({{nx, ny}, i});
                }
                else
                {
                    dq.push_back({{nx, ny}, i});
                }
            }
        }
    }
    cout << -1 << endl;
}

signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int t = 1;
    // cin >> t;
    while (t--)
    {
        solve();
    }
    return 0;
}