CF1264C.Beautiful Mirrors with queries

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题目描述

Creatnx has nn mirrors, numbered from 11 to nn . Every day, Creatnx asks exactly one mirror "Am I beautiful?". The ii -th mirror will tell Creatnx that he is beautiful with probability pi100\frac{p_i}{100} for all 1in1 \le i \le n .

Some mirrors are called checkpoints. Initially, only the 11 st mirror is a checkpoint. It remains a checkpoint all the time.

Creatnx asks the mirrors one by one, starting from the 11 -st mirror. Every day, if he asks ii -th mirror, there are two possibilities:

  • The ii -th mirror tells Creatnx that he is beautiful. In this case, if i=ni = n Creatnx will stop and become happy, otherwise he will continue asking the i+1i+1 -th mirror next day;
  • In the other case, Creatnx will feel upset. The next day, Creatnx will start asking from the checkpoint with a maximal number that is less or equal to ii .

There are some changes occur over time: some mirrors become new checkpoints and some mirrors are no longer checkpoints. You are given qq queries, each query is represented by an integer uu : If the uu -th mirror isn't a checkpoint then we set it as a checkpoint. Otherwise, the uu -th mirror is no longer a checkpoint.

After each query, you need to calculate the expected number of days until Creatnx becomes happy.

Each of this numbers should be found by modulo 998244353998244353 . Formally, let M=998244353M = 998244353 . It can be shown that the answer can be expressed as an irreducible fraction pq\frac{p}{q} , where pp and qq are integers and q≢0(modM)q \not \equiv 0 \pmod{M} . Output the integer equal to pq1modMp \cdot q^{-1} \bmod M . In other words, output such an integer xx that 0x<M0 \le x < M and xqp(modM)x \cdot q \equiv p \pmod{M} .

输入格式

The first line contains two integers nn , qq ( 2n,q21052 \leq n, q \le 2 \cdot 10^5 ) — the number of mirrors and queries.

The second line contains nn integers: p1,p2,,pnp_1, p_2, \ldots, p_n ( 1pi1001 \leq p_i \leq 100 ).

Each of qq following lines contains a single integer uu ( 2un2 \leq u \leq n ) — next query.

输出格式

Print qq numbers – the answers after each query by modulo 998244353998244353 .

输入输出样例

  • 输入#1

    2 2
    50 50
    2
    2
    

    输出#1

    4
    6
    
  • 输入#2

    5 5
    10 20 30 40 50
    2
    3
    4
    5
    3
    

    输出#2

    117
    665496274
    332748143
    831870317
    499122211
    

说明/提示

In the first test after the first query, the first and the second mirrors are checkpoints. Creatnx will ask the first mirror until it will say that he is beautiful, after that he will ask the second mirror until it will say that he is beautiful because the second mirror is a checkpoint. After that, he will become happy. Probabilities that the mirrors will say, that he is beautiful are equal to 12\frac{1}{2} . So, the expected number of days, until one mirror will say, that he is beautiful is equal to 22 and the answer will be equal to 4=2+24 = 2 + 2 .

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