floodfill.py

width, height  = raw_input().split()
width, height = int(width), int(height)
maze = []

for i in xrange(height):
  maze.append(list(raw_input()))

startx, starty, color = raw_input().split()
startx, starty = int(startx), int(starty)

target = maze[startx][starty]
dirs = ((0, 1), (0, -1), (1, 0), (-1, 0))
queue = []
visited = {}

queue.append((startx, starty))

while len(queue) > 0:
  x,y = queue.pop(0)

  if not visited.get((x, y), False) and maze[y][x] == target:
    visited[(x, y)] = True
    maze[y][x] = color
    neighbours = [((x+dx) % width, (y+dy) % height) for dx,dy in dirs]
    queue.extend(neighbours)

for line in maze:
  print ''.join(line)