#!/bin/python3

# Note this solution times out on test case 9 with Python3.

# However, this solution passes test case 9 with Pypy3.

from collections import deque

class CastleOnGrid:

CELL_BLOCKED_TOKEN = 'X'

def __init__(self, grid, grid_size, start, goal):

self.grid = grid

self.grid_size = grid_size

self.start = start

self.goal = goal

self.to_visit = deque()

self.visited = []

def min_moves(self):

self.to_visit.append((self.start, 0))

self.visited.append(self.start)

current_coords = None

while current_coords != self.goal:

current_coords, current_depth = self.to_visit.popleft()

for move in self.possible_moves(current_coords):

# This is an optimization necessary to avoid timeouts on test

# case 11.

if move == self.goal:

return current_depth + 1

else:

self.to_visit.append((move, current_depth + 1))

self.visited.append(move)

return current_depth

def possible_moves(self, coords):

row, col = coords

for row_i in range(row + 1, self.grid_size):

if self.grid[row_i][col] == self.CELL_BLOCKED_TOKEN:

break

elif (row_i, col) in self.visited:

continue

else:

yield (row_i, col)

for row_i in range(row - 1, -1, -1):

if self.grid[row_i][col] == self.CELL_BLOCKED_TOKEN:

break

elif (row_i, col) in self.visited:

continue

else:

yield (row_i, col)

for col_i in range(col + 1, self.grid_size):

if self.grid[row][col_i] == self.CELL_BLOCKED_TOKEN:

break

elif (row, col_i) in self.visited:

continue

else:

yield (row, col_i)

for col_i in range(col - 1, -1, -1):

if self.grid[row][col_i] == self.CELL_BLOCKED_TOKEN:

break

elif (row, col_i) in self.visited:

continue

else:

yield (row, col_i)

if __name__ == '__main__':

grid_size = int(input())

grid = []

for _ in range(grid_size):

grid.append(list(input()))

coords = list(map(int, input().split()))

start = (coords[0], coords[1])

goal = (coords[2], coords[3])

castle_on_grid = CastleOnGrid(grid, grid_size, start, goal)

print(castle_on_grid.min_moves())