[Ruby] leetCode - 1138. Alphabet Board Path
題目 轉自 leetCode On an alphabet board, we start at position (0, 0), corresponding to character board[0][0]. Here, board = ["abcde", "fghij", "klmno", "pqrst", "uvwxy", "z"], as shown in the diagram below. We may make the following moves: `'U'` moves »