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题目： You are given an array A , and Zhu wants to know there are how many different array B satisfy the following conditions? * 1≤Bi≤Ai * For each pair( l , r ) (1≤l≤r≤n) , gcd(bl,bl+1…br)≥2 Input

题目 You are given array ai of length n. You may consecutively apply two operations to this array: remove some subsegment (continuous subsequence) of length m < n and pay for it m·a coins change some el

题目： Squirrel Liss is interested in sequences. She also has preferences of integers. She thinks n integers a1, a2, …, an are good.Now she is interested in good sequences. A sequence x1, x2, …, xk is ca