黑暗爆炸OJ
DARKBZOJ
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Description
2021. Moving Pebbles
Two players play the following game. At the beginning of the game they start with n (1<=n<=100000) piles of stones. At each step of the game, the player chooses a pile and remove at least one stone from this pile and move zero or more stones from this pile to any other pile that still has stones. A player loses if he has no more possible moves. Given the initial piles, determine who wins: the first player, or the second player, if both play perfectly.
给你N堆Stone,两个人玩游戏.
每次任选一堆,首先拿掉至少一个石头,然后移动任意个石子到任意堆中.
谁不能移动了,谁就输了...
Input
Each line of input has integers 0 < n <= 100000, followed by n positive integers denoting the initial piles.
Output
For each line of input, output "first player" if first player can force a win, or "second player", if the second player can force a win.
Sample Input
3 2 1 3
Sample Output
first player
Hint
鸣谢lqp18_31..Source