while True:
	try:
		data = input().split(' ')
	except:
		exit(0)	
	M, N = int(data[0]), int(data[1])
	if M == 0 and N == 0:
		exit(0)
	char = data[2][1]
	frameA = list()
	for x in range(M):
		frameA.append(input())

	frameB = list()
	for x in range(M):
		frameB.append(input())
	falcon_start = None
	falcon_end = None

	pattern = list()
	output = list()

	for x in range(M):
		output.append(list())
		pattern.append(list())
		for y in range(N):
			ca = frameA[x][y]
			cb = frameB[x][y]
			if ca == char:
				pattern[x].append(y)
				if falcon_start == None:
					falcon_start = [x,y]
				if cb != char:
					output[x].append(cb)
					
					
			else:
				output[x].append(ca)

			if cb == char:
				if falcon_end == None:
					falcon_end = [x,y]


	vec = [
		falcon_end[0] - falcon_start[0],
		falcon_end[1] - falcon_start[1]
	]

	for x in range(M):
		for y in pattern[x]:
			coord = [x + vec[0]*2,y + vec[1]*2]
			if 0 <= coord[0] < M and 0 <= coord[1] < N:
				output[coord[0]][coord[1]] = char

	for line in output:
		for c in line:
			print(c, end = '')

		print()