CF1227F1.Wrong Answer on test 233 (Easy Version)

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题目描述

Your program fails again. This time it gets "Wrong answer on test 233"

.This is the easier version of the problem. In this version 1n20001 \le n \le 2000 . You can hack this problem only if you solve and lock both problems.

The problem is about a test containing nn one-choice-questions. Each of the questions contains kk options, and only one of them is correct. The answer to the ii -th question is hih_{i} , and if your answer of the question ii is hih_{i} , you earn 11 point, otherwise, you earn 00 points for this question. The values h1,h2,,hnh_1, h_2, \dots, h_n are known to you in this problem.

However, you have a mistake in your program. It moves the answer clockwise! Consider all the nn answers are written in a circle. Due to the mistake in your program, they are shifted by one cyclically.

Formally, the mistake moves the answer for the question ii to the question imodn+1i \bmod n + 1 . So it moves the answer for the question 11 to question 22 , the answer for the question 22 to the question 33 , ..., the answer for the question nn to the question 11 .

We call all the nn answers together an answer suit. There are knk^n possible answer suits in total.

You're wondering, how many answer suits satisfy the following condition: after moving clockwise by 11 , the total number of points of the new answer suit is strictly larger than the number of points of the old one. You need to find the answer modulo 998244353998\,244\,353 .

For example, if n=5n = 5 , and your answer suit is a=[1,2,3,4,5]a=[1,2,3,4,5] , it will submitted as a=[5,1,2,3,4]a'=[5,1,2,3,4] because of a mistake. If the correct answer suit is h=[5,2,2,3,4]h=[5,2,2,3,4] , the answer suit aa earns 11 point and the answer suite aa' earns 44 points. Since 4>14 > 1 , the answer suit a=[1,2,3,4,5]a=[1,2,3,4,5] should be counted.

输入格式

The first line contains two integers nn , kk ( 1n20001 \le n \le 2000 , 1k1091 \le k \le 10^9 ) — the number of questions and the number of possible answers to each question.

The following line contains nn integers h1,h2,,hnh_1, h_2, \dots, h_n , ( 1hik)1 \le h_{i} \le k) — answers to the questions.

输出格式

Output one integer: the number of answers suits satisfying the given condition, modulo 998244353998\,244\,353 .

输入输出样例

  • 输入#1

    3 3
    1 3 1
    

    输出#1

    9
    
  • 输入#2

    5 5
    1 1 4 2 2
    

    输出#2

    1000
    

说明/提示

For the first example, valid answer suits are [2,1,1],[2,1,2],[2,1,3],[3,1,1],[3,1,2],[3,1,3],[3,2,1],[3,2,2],[3,2,3][2,1,1], [2,1,2], [2,1,3], [3,1,1], [3,1,2], [3,1,3], [3,2,1], [3,2,2], [3,2,3] .

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