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…
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…
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…
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…
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…
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…
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…
F. Successione di Fixoracci 题目链接:https://ac.nowcoder.com/acm/contest/912/F 题目: 动态规划(Dynamic programming,简称dp)是一种通过把原问题分解为相对简单的子问题的方式求解复杂问题的方法.例如,假设小x一步能爬1层或2层台阶,求小x爬n层台阶共有几种方法,就可以用dp计算:设Fi代表小x爬i层台阶共有几种方法,则Fi=Fi−1+Fi−2. 小x是练习时长两年半的acm练习生,喜欢口胡.dp.线段树.妙…
