4. The Wolf and the Hare are playing the following game: a number is written on the board, and a move consists of subtracting any non-zero digit of the number and writing the resulting number in place of the old one. They take turns. The one who gets zero wins. Initially, the number 1234 is written on the board. The Wolf moves first. Who will win with correct play?
90.4. The Wolf wins. For this, it is enough for him to subtract the last digit of the number on each of his moves, making it divisible by 10.