AmazingCounters.com
  2017年3月6日
摘要: FallDream dalao找的插值练习题 题目大意:给定n,k,求Σi^k (i=1~n),对1e9+7取模。(n<=10^9,k<=10^6) 思路:令f(n)=Σi^k (i=1~n),则有f(n)-f(n-1)=n^k,说明f(n)的差分是n的k次多项式,则所求f(n)为n的k+1次多项式 阅读全文
posted @ 2017-03-06 11:28 ditoly 阅读(195) 评论(0) 推荐(0) 编辑
摘要: Codeforces #403 Div1.A~D(Div2.B~F)简要题解 [ Div2.B.The Meeting Place Cannot Be Changed | A.Andryusha and Colored Balloons | B.Innokenty and a Football League | C.Underground Lab | D. Axel and Marston in Bitland ] 阅读全文
posted @ 2017-03-06 10:10 ditoly 阅读(110) 评论(0) 推荐(0) 编辑