D.New Year Concert 传送门 题目大意: 一个长为 N ( 1 ≤ N ≤ 2 × 1 0 5 ) N(1\leq N\leq2\times 10^5) N(1≤N≤2×105)的序列 A A A,对于 [ l , r ] [l,r] [l,r],如果 g c d ( A l , A l + 1 , . . . , A r ) = r − l + 1 gcd(A_{l},A_{l+1},...,A_{r})=r-l+1 gcd(Al,Al+1,...,Ar)=r−l+1,称…