CF891E Lust
Description
A false witness that speaketh lies!
You are given a sequence containing $ n $ integers. There is a variable $ res $ that is equal to $ 0 $ initially. The following process repeats $ k $ times.
Choose an index from $ 1 $ to $ n $ uniformly at random. Name it $ x $ . Add to $ res $ the multiply of all $ a_{i} $ 's such that $ 1
Input Format
N/A
Output Format
N/A