International Olympiad
International Abbreviation Olympiad takes place annually starting from 1989. Each year the competition receives an abbreviation of form IAO’y, where y stands for some number of consequent last […]
ACM
Little Artem and Grasshopper
Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of […]
Little Artem and Matrix
Little Artem likes electronics. He can spend lots of time making different schemas and looking for novelties in the nearest electronics store. The new control […]
Little Artem and Time Machine
Little Artem has invented a time machine! He could go anywhere in time, but all his thoughts of course are with computer science. He wants […]
Little Artem and Dance
Little Artem is fond of dancing. Most of all dances Artem likes rueda — Cuban dance that is danced by pairs of boys and girls forming […]
Little Artem and Random Variable
Little Artyom decided to study probability theory. He found a book with a lot of nice exercises and now wants you to help him with […]
Little Artem and 2-SAT
Little Artem is a very smart programmer. He knows many different difficult algorithms. Recently he has mastered in 2-SAT one. In computer science, 2-satisfiability (abbreviated as 2-SAT) is […]
Bear and Colors
Bear Limak has n colored balls, arranged in one long row. Balls are numbered 1 through n, from left to right. There are n possible colors, also numbered 1 through n. The i-th ball has color t i. […]
Bear and Two Paths
Bearland has n cities, numbered 1 through n. Cities are connected via bidirectional roads. Each road connects two distinct cities. No two roads connect the same pair of cities. Bear […]
Bear and Destroying Subtrees
Limak is a little grizzly bear. He will once attack Deerland but now he can only destroy trees in role-playing games. Limak starts with a […]
Levels and Regions
Radewoosh is playing a computer game. There are n levels, numbered 1 through n. Levels are divided into k regions (groups). Each region contains some positive number of consecutive levels. The game […]
Bears and Juice
There are n bears in the inn and p places to sleep. Bears will party together for some number of nights (and days). Bears love drinking juice. They don’t […]
NP-Hard Problem
Recently, Pari and Arya did some research about NP-Hard problems and they found the minimum vertex cover problem very interesting. Suppose the graph G is given. Subset A of its vertices […]
Remainders Game
Today Pari and Arya are playing a game called Remainders. Pari chooses two positive integer x and k, and tells Arya k but not x. Arya have to find the value . […]
The Values You Can Make
Pari wants to buy an expensive chocolate from Arya. She has n coins, the value of the i-th coin is c i. The price of the chocolate is k, so Pari […]
Dividing Kingdom II
Long time ago, there was a great kingdom and it was being ruled by The Great Arya and Pari The Great. These two had some […]
Robbers’ watch
Robbers, who attacked the Gerda’s cab, are very successful in covering from the kingdom police. To make the goal of catching them even harder, they […]
Kay and Snowflake
After the piece of a devilish mirror hit the Kay’s eye, he is no longer interested in the beauty of the roses. Now he likes […]
Optimal Point
When the river brought Gerda to the house of the Old Lady who Knew Magic, this lady decided to make Gerda her daughter. She wants […]
