void update(int I, int J, int i, int j, vector<vector<bool>>& visited, vector<vector<int>>& minPath, queue<pair<int, int>>& Q) {
    if (visited[i][j]) return;
    visited[i][j] = true;
    minPath[i][j] = minPath[I][J] + 1;
    Q.push(make_pair(i, j));
    return;
}

int minimumMoves(int n, vector<vector<char>> grid, int startX, int startY, int goalX, int goalY) {
    vector<vector<bool>> visited(n + 2, vector<bool>(n + 2));
    vector<vector<int>> minPath(n + 2, vector<int>(n + 2, -1));
    queue<pair<int, int>> Q;
    Q.push(make_pair(startX, startY));
    visited[startX][startY] = true;
    minPath[startX][startY] = 0;
    while (!Q.empty()) {
        int I = Q.front().first, J = Q.front().second;
        for (int i=1; I - i > 0; i++) {
            if (grid[I-i][J] == 'X') break;
            update(I, J, I-i, J, visited, minPath, Q);
        }
        for (int i=1; I + i < n+1; i++) {
            if (grid[I+i][J] == 'X') break;
            update(I, J, I+i, J, visited, minPath, Q);
        }
        for (int j=1; J - j > 0; j++) {
            if (grid[I][J-j] == 'X') break;
            update(I, J, I, J-j, visited, minPath, Q);
        }
        for (int j=1; J + j < n+1; j++) {
            if (grid[I][J+j] == 'X') break;
            update(I, J, I, J+j, visited, minPath, Q);
        }
        Q.pop();
    }
    return minPath[goalX][goalY];
}

int main()
{
    int n, startX, startY, goalX, goalY;
    string s;
    cin >> n;
    vector<vector<char>> grid(n + 2, vector<char>(n + 2));
    for (int i = 1; i <= n; i++) {
        cin >> s;
        for (int j = 1; j <= n; j++) grid[i][j] = s[j - 1];
    }
    cin >> startX >> startY >> goalX >> goalY;
    cout << minimumMoves(n, grid, startX + 1, startY + 1, goalX + 1, goalY + 1);
}