B'You are given an array a of length n . Also you are given m distinct positions p_1, p_2, ldots, p_m ( 1 <= q p_i <= q n ). A non-empty subset of these positions T is randomly selected with equal probability and the following value is calculated: sum_{i=1}^{n} (a_i cdot min_{j in T} <= ft|i - j right|). In other word, for each index of the array, a_i and the distance to the closest chosen position are multiplied, and then these values are summed up. Find the expected value of this sum. This value must be found modulo 998 ,244 ,353 . More formally, let M = 998 ,244 ,353 . It can be shown that the answer can be represented as an irreducible fraction frac{p}{q} , where p and q are integers and q neq 0 (mod M ). Output the integer equal to p cdot q^{-1} (mod M ). In other words, output such integer x that 0 <= q x < M and x cdot q = p (mod M ). The first line contains two integers n and m ( 1 <= q m <= q n <= q 10^5 ). The second line contains n integers a_1, a_2, ldots, a_n ( 0 <= q a_i < 998 ,244 ,353 ). The third line contains m distinct integers p_1, p_2, ldots, p_m ( 1 <= q p_i <= n ). For every 1 <= q i < m it is guaranteed that p_i < p_{i+1} . Print a single integer -- the answer to the problem. In the first test: The answer to the problem is frac{20 + 10 + 5}{3} = frac{35}{3} = 665 ,496 ,247 (modulo 998 ,244 ,353 ). '...