摘要：
Description It is year 2500 A.D. and there is a terrible war between the forces of the Earth and the Mars. Recently, the commanders of the Earth are i 阅读全文
摘要：
题目链接： https://nanti.jisuanke.com/t/31458 题解： 建立两个树状数组，第一个是，a[1]*n+a[2]*(n-1)....+a[n]*1;第二个是正常的a[1],a[2],a[3]...a[n] 262144K Morgana is learning compu 阅读全文