Restore a Number

brute force, constructive algorithms, strings

Comfortably Numb

bitmasks, data structures, divide and conquer, strings, trees

Alphabet Permutations

data structures, strings

The Supersonic Rocket

geometry, hashing, strings

Autocompletion

*special problem, strings, trees

Rusty String

fft, math, strings

x-prime Substrings

brute force, dfs and similar, dp, string suffix structures, strings

Marbles

hashing, strings

Minus and Minus Give Plus

*special problem, implementation, strings

Two Permutations

data structures, hashing, strings

Codeword

combinatorics, strings

DZY Loves Strings

binary search, hashing, strings, two pointers

Diverse Substrings

dp, strings, two pointers

Birthday

graph matchings, strings

Minlexes

dp, greedy, implementation, strings

Calendar

greedy, strings

Name

greedy, strings

Xors on Segments

data structures, strings, trees

Mr. Kitayuta's Gift

combinatorics, dp, matrices, strings

Middle-Out

constructive algorithms, greedy, strings

Tricky and Clever Password

binary search, constructive algorithms, data structures, greedy, hashing, strings

Digits of Number Pi

dp, implementation, strings

Refactoring

greedy, implementation, strings

Have You Ever Heard About the Word?

greedy, hashing, string suffix structures, strings

Holiday Wall Ornaments

dp, strings

Mission Impassable

dp, strings

Elementary!

*special problem, brute force, dp, strings

Expensive Strings

string suffix structures, strings

Construct the String

data structures, dp, strings

Serval and Brain Power

bitmasks, brute force, dp, greedy, implementation, strings

And Yet Another Bracket Sequence

data structures, greedy, hashing, string suffix structures, strings

The Next Good String

data structures, greedy, hashing, strings

Gnikool Ssalg

*special problem, implementation, strings

Concatenation with intersection

data structures, hashing, strings, two pointers

Keyboard Design

bitmasks, data structures, dp, string suffix structures, strings

Writing a Song

brute force, dp, strings

Dreamoon and Binary

dp, strings

Fedya the Potter Strikes Back

data structures, strings

Dasha and cyclic table

bitmasks, brute force, fft, strings, trees

Similar Words

dp, hashing, strings, trees

String Transformation

hashing, strings

Au Pont Rouge

binary search, dp, strings

Scissors

brute force, strings

Puzzle Lover

dp, hashing, strings

Tree and XOR

strings, trees

String Distance

binary search, brute force, data structures, hashing, implementation, strings

Reverses

dp, string suffix structures, strings

Fake News (medium)

constructive algorithms, strings

Chainword

brute force, data structures, dp, matrices, string suffix structures, strings

Two Prefixes

strings

Arithmancy (Easy)

brute force, constructive algorithms, interactive, strings

Speed Dial

dp, strings, trees

Xenia and String Problem

dp, hashing, implementation, string suffix structures, strings

Wilbur and Strings

dfs and similar, dp, graphs, strings

Smart Boy

dp, games, strings

Twilight and Ancient Scroll (easier version)

dp, hashing, implementation, string suffix structures, strings

Appleman and a Game

binary search, shortest paths, strings

Palindrome

implementation, strings

A task for substrings

data structures, string suffix structures, strings

Twilight and Ancient Scroll (harder version)

dp, hashing, implementation, string suffix structures, strings, two pointers

Shrink-Reverse

binary search, brute force, greedy, hashing, implementation, string suffix structures, strings

Bosco and Particle

dp, math, number theory, strings

In Every Generation...

*special problem, strings

Find String in a Grid

data structures, dp, strings, trees

The Sum of Good Numbers

hashing, math, string suffix structures, strings

Pumping Lemma

hashing, strings

AB-Strings

constructive algorithms, strings

Representative Sampling

dp, sortings, strings

World of Mouth

*special problem, strings

Wrap Around

dp, strings

Palindromic Problem

binary search, data structures, hashing, string suffix structures, strings

Modest Substrings

dp, strings

Expected Value Again

combinatorics, strings

Fibonacci Suffix

strings

Palindrome Addicts

data structures, strings

Ж-function

string suffix structures, strings

Prefixes and Suffixes

*special problem, strings

Speckled Band

data structures, divide and conquer, hashing, string suffix structures, strings

Six Characters

*special problem, constructive algorithms, strings

Mahmoud and Ehab and the final stage

data structures, strings

Entangled Substrings

string suffix structures, strings

Fibonacci Strings

matrices, strings

Moonwalk challenge

data structures, strings, trees

Fibonacci Strings

strings

Cutting the Line

string suffix structures, strings

Alphabetic Tree

binary search, data structures, dfs and similar, hashing, string suffix structures, strings, trees

Ali goes shopping

*special problem, brute force, strings

Detect Robots

data structures, strings

Rap God

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

Hongcow Masters the Cyclic Shift

strings, two pointers

Toys

greedy, strings

Boboniu and Banknote Collection

strings

Arithmancy (Medium)

constructive algorithms, interactive, probabilities, strings

Upside Down

data structures, string suffix structures, strings, trees

kotlinkotlinkotlinkotlin...

*special problem, graphs, implementation, strings

String Theory

geometry, math, strings

Palindromic Magic

data structures, hashing, strings

Mio and Lucky Array

constructive algorithms, fft, math, strings

Mateusz and an Infinite Sequence

bitmasks, brute force, dp, strings

Suffix Subgroup

*special problem, strings