A Diverse Team
There are n students in a school class, the rating of the i-th student on Codehorses is ai. You have to form a team consisting of k students (1≤k≤n) such that the ratings of all team members are distinct.
If it is impossible to for >>继续阅读
A Infinity Gauntlet
You took a peek on Thanos wearing Infinity Gauntlet. In the Gauntlet there is a place for six Infinity Gems:
the Power Gem of purple color, the Time Gem of green color, the Space Gem of blue color, the Soul Gem of orange color >>继续阅读
A Move and Win
A game is played on a strip consisting of N cells consecutively numbered from 1 to N.
Alice has her token on cell A. Borys has his token on a different cell B.
Players take turns, Alice moves first. The moving player must shift h >>继续阅读
A Garden
Luba thinks about watering her garden. The garden can be represented as a segment of length k. Luba has got n buckets, the i-th bucket allows her to water some continuous subsegment of garden of length exactly ai each hour. Luba can't wate >>继续阅读
A Modular Exponentiation
The following problem is well-known: given integers n and m, calculate,
where 2n = 2·2·...·2 (n factors), and denotes the remainder of division of x by y.
You are asked to solve the "reverse" problem. Given integers n a >>继续阅读
A Tricky Alchemy
During the winter holidays, the demand for Christmas balls is exceptionally high. Since it's already 2018, the advances in alchemy allow easy and efficient ball creation by utilizing magic crystals.
Grisha needs to obtain some ye >>继续阅读
A Elephant
An elephant decided to visit his friend. It turned out that the elephant's house is located at point 0 and his friend's house is located at point x(x > 0) of the coordinate line. In one step the elephant >>继续阅读
250 Problem Statement
You have two favorite music bands. Each of them has just recorded a new album. You have bought both albums.
You know the durations (in seconds) of songs on each of >>继续阅读
250 Problem Statement
A positive integer is called a prime if it has exactly two distinct positive integer divisors: 1 and itself. The first few primes are 2, 3, 5, 7, 11, 13, ...
A positive integer is called a palindrome if its base-10 represent >>继续阅读
A N bulbs
Problem Description
N bulbs are in a row from left to right,some are on, and some are off.The first bulb is the most left one. And the last one is the most right one.they are numbered from 1 to n,from left to right. >>继续阅读
A Saitama Destroys Hotel
Saitama accidentally destroyed a hotel again. To repay the hotel company, Genos has volunteered to operate an elevator in one of its other hotels. The elevator is special — it starts on the top floor, can only move down, an >>继续阅读
250 Problem Statement
Farmer John recently found out about a popular online farming game.There are n types of plants in the game. The types are numbered 0 through n-1. At the beginning of the game, Farmer John is given one seed of each plant type.T >>继续阅读
A ZYB's Biology
Problem Description
After getting 600 scores in NOIP ZYB(ZJ-267) begins to work with biological questions.Now he give you a simple >>继续阅读
A Uncowed Forces
Kevin Sun has just finished competing in Codeforces Round #334! The round was 120 minutes long and featured five problems with maximum point values of 500, 1000, 1500, 2000, and 2500, respectively. Despite the challenging tasks, Ke >>继续阅读
A Numbers
Problem Description
There is a number N.You should output "YES" if N is a multiple of 2, 3 or 5,otherwise output "NO". >>继续阅读
