NOIP2023模拟13联测34 A. origenNOIP2023模拟13联测34 A. origen给定 n n n 个整数 a 1 , a 2 , a 3 ⋯ a n a_1,a_2,a_3\cdots a_n a1,a2,a3⋯an ，求 ∑ i = 1 n ∑ j = i n ( ⊕ k = i j a k ) 2 m o d 998244353 \sum_{i = 1}^n\sum_{j = i}^n(\oplus_{k = i}^ja_k)^2 \mod 998244353 i=1∑nj=i∑n(⊕k=ijak)2mod998244353 n ≤ 2 ∗ 1 0 5 , 0 ≤ a i