摘要: Sol 由于 \(f(a,b,c)=\sum\limits_{i=1}^{|a|}\sum\limits_{j=i}^{|a|}\sum\limits_{k=1}^{|b|}\sum\limits_{l=k}^{|b|}[a_{i,i+1,\cdots,j}+b_{k,k+1,\cdots,l} = 阅读全文
posted @ 2025-11-20 19:23 tmp_get_zip_diff 阅读(11) 评论(0) 推荐(0)