CF1106F.Lunar New Year and a Recursive Sequence

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题目描述

Lunar New Year is approaching, and Bob received a gift from his friend recently — a recursive sequence! He loves this sequence very much and wants to play with it.

Let f1,f2,,fi,f_1, f_2, \ldots, f_i, \ldots be an infinite sequence of positive integers. Bob knows that for i>ki > k , fif_i can be obtained by the following recursive equation:

$$f_i = \left(f_{i - 1} ^ {b_1} \cdot f_{i - 2} ^ {b_2} \cdot \cdots \cdot f_{i - k} ^ {b_k}\right) \bmod p, $$ </p><p>which in short is</p><p> $$ f_i = \left(\prod_{j = 1}^{k} f_{i - j}^{b_j}\right) \bmod p, $$ </p><p>where $p = 998\\,244\\,353$ (a widely-used prime), $b\_1, b\_2, \\ldots, b\_k$ are known integer constants, and $x \\bmod y$ denotes the remainder of $x$ divided by $y$ .</p><p>Bob lost the values of $f\_1, f\_2, \\ldots, f\_k$ , which is extremely troublesome – these are the basis of the sequence! Luckily, Bob remembers the first $k - 1$ elements of the sequence: $f\_1 = f\_2 = \\ldots = f\_{k - 1} = 1$ and the $n$ -th element: $f\_n = m$ . Please find any possible value of $f\_k$$$. If no solution exists, just tell Bob that it is impossible to recover his favorite sequence, regardless of Bob's sadness.

输入格式

The first line contains a positive integer kk ( 1k1001 \leq k \leq 100 ), denoting the length of the sequence b1,b2,,bkb_1, b_2, \ldots, b_k .

The second line contains kk positive integers b1,b2,,bkb_1, b_2, \ldots, b_k ( 1bi<p1 \leq b_i < p ).

The third line contains two positive integers nn and mm ( k<n109k < n \leq 10^9 , 1m<p1 \leq m < p ), which implies fn=mf_n = m .

输出格式

Output a possible value of fkf_k , where fkf_k is a positive integer satisfying 1fk<p1 \leq f_k < p . If there are multiple answers, print any of them. If no such fkf_k makes fn=mf_n = m , output 1-1 instead.

It is easy to show that if there are some possible values of fkf_k , there must be at least one satisfying 1fk<p1 \leq f_k < p .

输入输出样例

  • 输入#1

    3
    2 3 5
    4 16
    

    输出#1

    4
    
  • 输入#2

    5
    4 7 1 5 6
    7 14187219
    

    输出#2

    6
    
  • 输入#3

    8
    2 3 5 6 1 7 9 10
    23333 1
    

    输出#3

    1
    
  • 输入#4

    1
    2
    88888 66666
    

    输出#4

    -1
    
  • 输入#5

    3
    998244352 998244352 998244352
    4 2
    

    输出#5

    -1
    
  • 输入#6

    10
    283 463 213 777 346 201 463 283 102 999
    2333333 6263423
    

    输出#6

    382480067
    

说明/提示

In the first sample, we have f4=f32f23f15f_4 = f_3^2 \cdot f_2^3 \cdot f_1^5 . Therefore, applying f3=4f_3 = 4 , we have f4=16f_4 = 16 . Note that there can be multiple answers.

In the third sample, applying f7=1f_7 = 1 makes f23333=1f_{23333} = 1 .

In the fourth sample, no such f1f_1 makes f88888=66666f_{88888} = 66666 . Therefore, we output 1-1 instead.

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