def is_valid(grid, i, j):
    return i >=0 and i < len(grid) and j >=0 and j < len(grid[i]) and grid[i][j] != 'X'
    
def span(grid, x, y, graph):
    i, j = x+1, y
    while is_valid(grid, i, j):
        graph[(x, y)].add((i, j))
        i = i+1
    
    i, j = x-1, y
    while is_valid(grid, i, j):
        graph[(x, y)].add((i, j))
        i = i-1
        
    i, j = x, y+1
    while is_valid(grid, i, j):
        graph[(x, y)].add((i, j))
        j = j+1
    
    i, j = x, y-1
    while is_valid(grid, i, j):
        graph[(x, y)].add((i, j))
        j = j-1
    
def build_graph(grid):
    graph = {}
    for i in range(len(grid)):
        for j in range(len(grid[i])):
            if (grid[i][j] != 'X'):
                graph[(i, j)] = set()
                span(grid, i, j, graph)
    return graph

def bfs(start, end, graph):
    q1 = deque()
    q2 = deque()
    
    visited = set()
    
    q1.append(start)
    depth = 0
    
    while len(q1) > 0:
        v = q1.popleft()
        if v == end:
            return depth
        for adj in graph[v]:
            if adj not in visited:
                visited.add(adj)
                q2.append(adj)
        if len(q1) == 0 and len(q2) > 0:
            depth = depth + 1
            q1, q2 = q2, q1
    
    return depth

def minimumMoves(grid, startX, startY, goalX, goalY):
    graph = build_graph(grid)
    start = (startX, startY)
    end = (goalX, goalY)
    return bfs(start, end, graph)