CF888E Maximum Subsequence

You are given an array $ a $ consisting of $ n $ integers, and additionally an integer $ m $ . You have to choose some sequence of indices $ b_{1},b_{2},...,b_{k} $ ( $ 1

N/A

N/A

In the first example you can choose a sequence $ b={1,2} $ , so the sum  is equal to $ 7 $ (and that's $ 3 $ after taking it modulo $ 4 $ ). In the second example you can choose a sequence $ b={3} $ .