zk has n numbers a1,a2,...,ana1,a2,...,an. For each (i,j) satisfying 1≤i<j≤n, zk generates a new number (ai+aj)(ai+aj). These new numbers could make up a new sequence b1,b2,...,bn(n−1)/2b1,b2,...,bn(n−1)/2.  LsF wants to make some trouble. While zk i…

LsF is visiting a local amusement park with his friends, and a mirror room successfully attracts his attention. Inside the mirror room, there are n plane mirrors standing vertically on the ground. They are placed end-to-end and face-to-face so that i…

Senior Pan fails in his discrete math exam again. So he asks Master ZKC to give him graph theory problems everyday.  The task is simple : ZKC will give Pan a directed graph every time, and selects some nodes from that graph, you can calculate the min…

Giving two strings and you should judge if they are matched.  The first string contains lowercase letters and uppercase letters.  The second string contains lowercase letters, uppercase letters, and special symbols: "." and "*".  . can…

At Valentine's eve, Shylock and Lucar were enjoying their time as any other couples. Suddenly, LSH, Boss of FFF Group caught both of them, and locked them into two separate cells of the jail randomly. But as the saying goes: There is always a way out…

Mr. Cui is working off-campus and he misses his girl friend very much. After a whole night tossing and turning, he decides to get to his girl friend's city and of course, with well-chosen gifts. He knows neither too low the price could a gift be sinc…

You are given a complete binary tree with n nodes. The root node is numbered 1, and node x's father node is ⌊x/2⌋⌊x/2⌋. At the beginning, node x has a value of exactly x. We define the value of a path as the sum of all nodes it passes(including two e…

2018 ACM 国际大学生程序设计竞赛上海大都会赛重现赛 J Beautiful Numbers (数位DP) 链接:https://ac.nowcoder.com/acm/contest/163/J?&headNav=acm来源:牛客网 时间限制:C/C++ 8秒,其他语言16秒 空间限制:C/C++ 262144K,其他语言524288K 64bit IO Format: %lld 题目描述 NIBGNAUK is an odd boy and his taste is strange a…

题目链接:https://ac.nowcoder.com/acm/contest/163/J 题目大意:给定一个数N,求区间[1,N]中满足可以整除它各个数位之和的数的个数.(1 ≤ N ≤ 1012). 输入: 21018 输出: Case 1: 10Case 2: 12 解题思路:比较简单的一道数位dp题,因为N的范围最大可为10的十二次方,即数位和的范围为[1,108],1-108的最小公倍数很大不可求,所以我们直接暴力枚举数位和为1-108的情况,然后利用数位dp求出合法数的个数就可以了…

题意: 数竞选手小r最喜欢做的题型是数列大题,并且每一道都能得到满分. 你可能不相信,但其实他发现了一个结论:只要是数列,无论是给了通项还是给了递推式,无论定义多复杂,都可以被搞成等差数列.这样,只要他精通了等差数列,他就能做出任何数列题目. 等差数列是数列的一种.在等差数列中,任何相邻两项的差相等,该差值称为公差.例如数列3,5,7,9,11,13,⋯3,5,7,9,11,13,⋯就是一个等差数列. 在这个数列中,从第二项起,每项与其前一项之差都等于2,即公差为2. 小r熟知等差数列的各种公式…