Calendar Reform

*special problem, number theory

Bus

*special problem, implementation, sortings

Pseudorandom Sequence Period

*special problem, implementation, number theory

Phone Code

*special problem, brute force, implementation

A polyline

*special problem, implementation

Mysterious numbers - 2

*special problem

ucyhf

*special problem, brute force, implementation, number theory

MYSTERIOUS LANGUAGE

*special problem

Broken checker

*special problem, brute force

A Piece of Cake

*special problem, implementation

Star

*special problem, combinatorics

Mysterious numbers - 1

*special problem, constructive algorithms

Replacing Digits

greedy

Chores

sortings

Wizards and Minimal Spell

implementation, strings

Wizards and Demonstration

implementation, math

Wizards and Bets

dfs and similar, graphs, math, matrices

Wizards and Roads

data structures, divide and conquer, graph matchings, graphs, greedy

Wizards and Numbers

games, math

Wizards and Huge Prize

dp, math, probabilities

Wizards and Trolleybuses

implementation, math

Tetrahedron

dp, math, matrices

Shoe Store

dp, graph matchings, greedy, sortings, two pointers

Median

greedy, math, sortings

Polygons

geometry, sortings

Rank List

binary search, implementation, sortings

Compatible Numbers

bitmasks, brute force, dfs and similar, dp

Beard Graph

data structures, dsu, trees

Another Problem on Strings

binary search, brute force, dp, math, strings, two pointers

Burning Midnight Oil

binary search, implementation

Supercentral Point

implementation

Polycarpus and Tasks

Minimum Diameter

binary search, brute force

Machine Programming

flows, graphs

Ancient Berland Hieroglyphs

two pointers

Variable, or There and Back Again

dfs and similar, graphs

e-Government

data structures, dfs and similar, dp, strings, trees

Large Refrigerator

brute force

Conveyor

sortings, two pointers

Lemmings

binary search

Substring and Subsequence

dp

Brackets

*special problem

Truncatable primes

*special problem

Alternating case

*special problem

Non-decimal sum

*special problem

Factorial zeros

*special problem

HQ9+

*special problem

Remove digits

*special problem

Prime factorization

*special problem

Binary notation

*special problem

Pentagonal numbers

*special problem, implementation

Polycarpus the Safecracker

brute force, dp

Distance in Tree

dfs and similar, dp, trees

Abracadabra

divide and conquer

Discounts

constructive algorithms, greedy, sortings

Dress'em in Vests!

binary search, brute force, greedy, two pointers

Buses and People

binary search, data structures, sortings

Edges in MST

dfs and similar, dsu, graphs, sortings

Find Pair

implementation, math, sortings

Unlucky Ticket

greedy, sortings

Twins

greedy, sortings

Zebra Tower

*special problem, data structures, greedy, sortings

Palindrome pairs

*special problem, brute force, dp, strings

String Manipulation 1.0

*special problem, binary search, brute force, data structures, strings

Matchmaker

*special problem, greedy, sortings

Friends or Not

*special problem, greedy, implementation

Phone Talks

*special problem, dp, sortings

Ice Sculptures

*special problem, brute force, number theory

Cd and pwd commands

*special problem, data structures, implementation

Taxi

*special problem, greedy, implementation

Next Round

*special problem, implementation

Trace

geometry, sortings

Game Outcome

brute force

Mrs. Hudson's Pancakes

brute force, dp

Clues

combinatorics, graphs

Cipher

combinatorics, dp

Suspects

constructive algorithms, data structures, implementation

Message

brute force

Combination

greedy, sortings

I_love_\%username\%

brute force

Martian Colony

geometry

Flatland Fencing

games, math

Double Profiles

graphs, hashing, sortings

Colliders

math, number theory

Hometask

greedy

Euclidean Distance

*special problem

Date Change

*special problem

Caesar Cipher

*special problem

Binary notation

*special problem

A + B

*special problem

Garden

bitmasks, dp, graphs, trees

Frames

brute force

Pocket Book

combinatorics

Steps

binary search, implementation

Marks

implementation

Phone Numbers

implementation, strings

Soft Drinking

implementation, math

Freezing with Style

binary search, data structures, divide and conquer, trees

Mission Impassable

dp, strings

Smart Cheater

data structures, math, probabilities