题目描述
Problem Statement
There are N cards numbered 1 to N. Card i has an integer A_i written on it.
Here, N is even.
Snuke and Robot will play a game, which will go as follows.
- The game master announces $a permutation (p_1,p_2,\cdots,p_N)$ of $(1,2,\cdots,N)$, to both Snuke and Robot.
- Then, Snuke and Robot alternately take turns, with Snuke going first.
Each turn goes as follows. - Snuke's turn: choose a remaining card of his choice and eat it.
-
Robot's turn: choose Card i with the largest p_i and burn it.
-
The game ends when there is no more card.
The final score of the game is the sum of integers written on the cards eaten by Snuke.
Snuke will play optimally to maximize the score.
There are N! permutations p of $(1,2,\cdots,N).$ Find the sum, modulo 998244353, of the final scores for all of these permutations.
Input
Input is given from Standard Input in the following format:
N
$A_1 A_2 \cdots A_N$
Output
Print the answer.
Constraints
- $1 \leq N \leq 10^6$
- N is even.
- $1 \leq A_i \leq 10^9$
- All values in input are integers.
Sample Input 1
2
1 2
Sample Output 1
4
Regardless of the permutation p, Snuke will eat Card 2.
Sample Input 2
4
1 100 10000 1000000
Sample Output 2
24200400
For example, when p=(3,1,4,2), the game will go as follows.
- Snuke eats Card 3.
- Robot burns Card 1.
- Snuke eats Card 4.
- Robot burns Card 2.
The score of the game here is 1010000.
Sample Input 3
10
866111664 178537096 844917655 218662351 383133839 231371336 353498483 865935868 472381277 579910117
Sample Output 3
710984634
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分