永夜莫明的博客

 Little A has come to college and majored in Computer and Science. Today he has learned bit-operations in Algorithm Lessons, and he got a problem as homework. Here is the problem: You are giving n ...

You are given two strings a and b consisting of lowercase English letters. A beautiful substring is defined as a substring of any length of string b such that the first and last letters of it are the ...

You are given a grid consisting of n rows each of which is dived into m columns. The rows are numbered from 1 to n from top to bottom, and the columns are numbered from 1 to m from left to right. Each...

题目描述给定一个长度为N的数列，A1, A2, ... AN，如果其中一段连续的子序列Ai, Ai+1, ... Aj(i <= j)之和是K的倍数，我们就称这个区间[i, j]是K倍区间。 你能求出数列中总共有多少个K倍区间吗？ 输入第一行包含两个整数N和K。(1 <= N, K <= 100000) 以下N行每行包含一个整数Ai。(1 <=...

Nim is a mathematical game of strategy in which two players take turns removing objects from distinct heaps. The game ends when one of the players is unable to remove object in his/her turn. This play...

题目链接：https://cn.vjudge.net/problem/ZOJ-3950If we represent a date in the format YYYY-MM-DD (for example, 2017-04-09), do you know how many 9s will appear in all the dates betweenY1-M1-D1andY2-M2...

https://ac.nowcoder.com/acm/contest/882/J当时开局ac率100%，然后就死磕这道题（主要是因为题目短，不想去读别的题），一发RE，一发MLE，然后放弃了……WJYTXDY当时的想法很朴素，就是对于每一个位置的前缀和，看在他左边比他小的前缀和的数量（很明显时间复杂度不行，k*1e9，当时抱着如果评测机跑的快的话，说不定……），因为有负数，所以加...