每个数据集合的第一行是两个整数W 和H，分别表示x 方向和y 方向瓷砖的数量。W 和H 都不超过20。在接下来的H 行中，每行包括W 个字符。-Each data set is the first line of the two integers W and H, says the number of ceramic tile x direction and y direction respectively. W and H are no more than 20. In the next H lines, each line includes W characters.