Levko and Array

binary search, dp

Levko and Array Recovery

greedy, implementation

Neatness

constructive algorithms, dfs and similar

Pair of Numbers

binary search, brute force, data structures, math, two pointers

Prime Number

math, number theory

Permutation

constructive algorithms, dp, math

Table

constructive algorithms, greedy, implementation

Dima and Kicks

brute force, dsu, graphs, implementation

Dima and Hares

dp, greedy

Dima and Containers

constructive algorithms, greedy, implementation

Dima and Text Messages

brute force, strings

Dima and Continuous Line

brute force, implementation

Flag Day

constructive algorithms, implementation

Group of Students

brute force, greedy, implementation

Xenia and String Problem

dp, hashing, implementation, string suffix structures, strings

Bags and Coins

bitmasks, constructive algorithms, dp, greedy

Compartments

combinatorics, constructive algorithms, greedy, implementation

Xenia and Hamming

implementation, math

Knight Tournament

data structures, dsu

Vasya and Public Transport

greedy, implementation

Vasya and Digital Root

constructive algorithms, implementation

Lucky Number Representation

constructive algorithms, dfs and similar, dp

Transferring Pyramid

dp

Vasya and Beautiful Arrays

brute force, dp, number theory

Game with Strings

bitmasks, dp, games

Vasya and Robot

brute force, greedy, math

Antichain

dp, graph matchings, greedy

Queue

constructive algorithms, dp

Find Maximum

implementation, math, number theory

Two Heaps

combinatorics, constructive algorithms, greedy, implementation, math, sortings

Domino

implementation, math

Jeff and Periods

implementation, sortings

Jeff and Digits

brute force, implementation, math

Jeff and Permutation

greedy

Jeff and Removing Periods

data structures

Jeff and Brackets

dp, matrices

Jeff and Furik

combinatorics, dp, probabilities

Jeff and Rounding

dp, greedy, implementation, math

Wrong Floyd

brute force, constructive algorithms, dfs and similar, graphs

Looking for Owls

binary search, data structures, geometry, hashing, sortings

Bombs

greedy, implementation, sortings

Resort

graphs

TL

brute force, greedy, implementation

Color the Fence

data structures, dp, greedy, implementation

Cinema Line

greedy, implementation

Pilgrims

dfs and similar, dp, trees

Turtles

dp, matrices

Subset Sums

brute force, data structures

Apple Tree

dfs and similar, number theory, trees

Mafia

binary search, math, sortings

Fixed Points

brute force, implementation, math

Difference Row

constructive algorithms, implementation, sortings

Doodle Jump

math, number theory

Robot Control

dp, graphs, shortest paths

Number Transformation II

greedy, math

Lucky Common Subsequence

dp, strings

Alice and Bob

games, math, number theory

Suffix Subgroup

*special problem, strings

Superstitions Inspection

*special problem

Black Cat Rush

*special problem

Chain Letter

*special problem, dfs and similar, graphs

Counting Fridays

*special problem

Triskaidekaphobia

*special problem

Expecting Trouble

*special problem, probabilities

Simple Molecules

brute force, graphs, math

Magnets

implementation

Pumping Stations

brute force, dfs and similar, divide and conquer, flows, graphs, greedy, trees

Water Tree

data structures, dfs and similar, graphs, trees

Read Time

binary search, greedy, two pointers

Alternating Current

data structures, greedy, implementation

Rational Resistance

math, number theory

Xenia and Tree

data structures, divide and conquer, trees

Xenia and Dominoes

bitmasks, dfs and similar, dp

Cupboard and Balloons

geometry

Xenia and Spies

brute force, greedy, implementation

Xenia and Divisors

greedy, implementation

Candies Game

constructive algorithms, greedy

Iahub and Xors

data structures

Iahub and Permutations

combinatorics, math

Bubble Sort Graph

binary search, data structures, dp

Tourist Problem

combinatorics, implementation, math

Maximal Area Quadrilateral

brute force, geometry

The Wall

math

Three Swaps

constructive algorithms, dfs and similar, greedy

Xenia and Bit Operations

data structures, trees

Xenia and Weights

constructive algorithms, dfs and similar, dp, graphs, greedy, shortest paths

Xenia and Ringroad

implementation

Helpful Maths

greedy, implementation, sortings, strings

Optimize!

data structures

GCD Table

chinese remainder theorem, math, number theory

Divisor Tree

brute force, number theory, trees

Book of Evil

dfs and similar, divide and conquer, dp, trees

Quiz

binary search, greedy, math, matrices, number theory

Routine Problem

greedy, math, number theory

Puzzles

greedy

Vasily the Bear and Painting Square

bitmasks, combinatorics, dp, implementation

Vasily the Bear and Beautiful Strings

combinatorics, math, number theory

Vasily the Bear and Sequence

brute force, greedy, implementation, number theory

Vasily the Bear and Fly

math

Vasily the Bear and Triangle

implementation, math