I find that the problems of the contests which ended recently have not been rated for a long time, can somebody rate all of them pls?
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive. If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive. Never use someone else's code, read the tutorials or...
Recently, Pari and Arya did some research about NP-Hard problems and they found theminimum vertex coverproblem very interesting. Suppose the graphGis given. SubsetAof its vertices is called avertex coverof this graph, if for each edgeuvthere is at least one endpoint of it in this set, i....
Coming up with a new problem isn't as easy as many people think. Sometimes it is hard enough to name it. We'll consider a titleoriginalif it doesn't occur as a substring in any titles of recent Codeforces problems. You've got the titles ofnlast problems — the strings, consisting of...
Are there any websites or tools one can use in getting reliable rating for codeforces problems? You should remember that the rating assigned to problems is estimated from an aggregate statistic, and not individual submissions — individual contributions to the difficulty estimate become less important...
We decided to create a better measure of problem difficulty, which we’ll call “problem rating”. Problem rating is an integral value, with higher problem ratings reflecting harder problems. In order for the rating to be meaningful, we made it mathematically compatible with user ratings. Technic...
Solutions to Codeforces Problems Codeforces Global Round 5 - 1/9 1237A - Balanced Rating Changes - Accepted 1237B - Balanced Tunnel - Accepted 1237C1 - Balanced Removals (Easier) - Accepted 1237C2 - Balanced Removals (Harder) - Wrong answer Educational Codeforces Round 72 - 0/6 1217A - Cre...
如何选择题目 How to Choose Problems 这一阶段主要目标是提高对问题的观察能力。做构造题可以针对性地训练这一点。 选择难度在自己 rating 到 rating+200 范围内的构造题 (tag: constructive algorithms),按照过题人数降序做题,比如 [1700,1900] 区间的就是下面这个链接: ...
题单:codeforces.com/problems 1612D. X-Magic Pair 题意(2 s) 给定一个整数对(a,b).现有两种操作:①令(a,b)=(|a−b|,b);②令(a,b)=(a,|a−b|).给定一个整数x,问若干次(可能为零次)操作后能否 s.t. a=x或b=x. 有t (1≤t≤1e4)组测试数据.每组测试数据输入三个整数a,b,x ...
原题指路: codeforces.com/problems 题意(2 ) 称平面上三个点 p,q,r 构成坏三元组, 如果 d(p,r)=d(p,q)+d(q,r) , 其中 d(p,q) 表示点 p 与点q 的Manhattan距离. 称整数序列 b=[b1,⋯,bm] 是好的, 如果 ∄ 相异的 i,j,k∈[1,n] s.t. 点(bi,i),(bj,j),(bk,k) 构成...