Rita and Sam play the following game with n sticks on a table. Each must remove 1, 2, 3, 4 or 5 sticks at a time on altemate tums, and no stick that is removed is put back on the table.The one who removes the last stick(or sticks) from the table wins. If Rita goes first, which of the following is a value of n such that Sam can always win no matter how Rita plays?
7
10
11
12
16
只能拿1,2,3,4,5;1+5=6,2+4=6,3+3=6,所以总数如果是6的倍数,那么一定是先走的人输,因为无论先走的人拿什么后走的人都可以凑成6.这样子的话后走的人永远是最后一个拿的。
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