201372: [AtCoder]ARC137 C - Distinct Numbers
Description
Score : $600$ points
Problem Statement
You are given a non-negative integer sequence of length $N$: $A=(A_1,A_2,\cdots,A_N)$. Here, all elements of $A$ are pairwise distinct.
Alice and Bob will play a game. They will alternately play a turn, with Alice going first. In each turn, the player does the operation below.
- Choose the largest element in $A$ at the moment, and replace it with a smaller non-negative integer. Here, all elements in $A$ must still be pairwise distinct after this operation.
The first player to be unable to do the operation loses. Determine the winner when both players play optimally.
Constraints
- $2 \leq N \leq 3 \times 10^5$
- $0 \leq A_1 < A_2 < \cdots < A_N \leq 10^9$
- All values in input are integers.
Input
Input is given from Standard Input in the following format:
$N$ $A_1$ $A_2$ $\cdots$ $A_N$
Output
If Alice wins, print Alice
; if Bob wins, print Bob
.
Sample Input 1
2 2 4
Sample Output 1
Alice
In Alice's first turn, she may replace $4$ with $0$, $1$, or $3$. If she replaces $4$ with $0$ or $1$, Bob's move in the next turn will make Alice unable to do the operation and lose. On the other hand, if she replaces $4$ with $3$, she can win regardless of Bob's subsequent moves. Thus, Alice wins in this input.
Sample Input 2
3 0 1 2
Sample Output 2
Bob