Question 31
Two players alternately write one digit at a time, from left to right. A player loses if, after his move, there is a sequence of digits $a_1, a_2, \dots, a_n$ such that there exists a positive integer $k$ for which the number $\overline{a_k a_{k+1} \dots a_n}$ is a multiple of $11$.
Which player can win regardless of how his opponent plays? (Russia 2003)
Which player can win regardless of how his opponent plays? (Russia 2003)