D. 0-1 MST Ujan has a lot of useless stuff in his drawers, a considerable part of which are his math notebooks: it is time to sort them out. ...

D. Nezzar and Board https://codeforces.com/contest/1478/problem/D 题解 题意为给出一个序列xi，你可以任意挑选两个数x，y将2·x-y加入序列中，询问在是否可以在序列中发现数k。 假设我们任意挑选4个数：x，y，p，q ...

题意：一个n个数码位的分数板，每一个数码位都是一个七段数码管，现在给出每个数码位的显示情况，问再点亮k段数码管的话能显示的最大的数是多少，如果不能构成一串数字，就输出-1. 答案允许有前导0，但是有前导0的时候答案长度必须要跟n一致 原题链接：https://codeforces ...

D. Yet Another Monster Killing Problem You play a computer game. In this game, you lead a party of 𝑚 heroes, and you have to clear a dungeon ...

D. Irreducible Anagrams time limit per test2 seconds memory limit per test256 megabytes Let's call two strings s and t anagrams of each other ...

D. 1-2-K Game time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output Alice and Bob play a game. ...

D. Secret Passwords One unknown hacker wants to get the admin's password of AtForces testing system, to get problems from the next contest. ...

C. Tile Painting Ujan has been lazy lately, but now has decided to bring his yard to good shape. Fi ...