Arithmancy (Medium)

constructive algorithms, interactive, probabilities, strings

Division + LCP (hard version)

binary search, brute force, data structures, dp, hashing, math, string suffix structures, strings

Folding Strip

constructive algorithms, greedy, strings

Shrink-Reverse

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

Matrix Rank (Hard Version)

combinatorics, dp, math, matrices, string suffix structures

Palindromic Problem

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

Pumping Lemma

hashing, strings

Sofia and Strings

data structures, greedy, sortings, strings, two pointers

Palindrome Partition

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

Entangled Substrings

string suffix structures, strings

Bosco and Particle

dp, math, number theory, strings

A task for substrings

data structures, string suffix structures, strings

Serval and Brain Power

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

Delicious Dessert

binary search, dsu, hashing, math, number theory, string suffix structures

Comfortably Numb

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

Hossam and Range Minimum Query

binary search, bitmasks, data structures, hashing, probabilities, strings, trees

Majority

combinatorics, dp, math, strings

Bracket Cost

binary search, data structures, divide and conquer, dp, greedy, strings

Keyboard Design

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

Palindrome Addicts

data structures, strings

Equal Binary Subsequences

constructive algorithms, geometry, greedy, implementation, strings

Prefixes and Suffixes

constructive algorithms, strings, two pointers

Prefix Function Queries

dfs and similar, dp, hashing, string suffix structures, strings, trees

Xor-Subsequence (hard version)

bitmasks, data structures, dp, strings, trees

Mio and Lucky Array

constructive algorithms, fft, math, strings

Text Editor

brute force, dp, greedy, strings

Typical Party in Dorm

bitmasks, combinatorics, dp, strings

Minimal String Xoration

bitmasks, data structures, divide and conquer, greedy, hashing, sortings, strings

Middle Duplication

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

Two Sequences

data structures, hashing, string suffix structures

Lexicographically Small Enough

brute force, data structures, greedy, strings

Alphabetic Tree

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

The Sum of Good Numbers

hashing, math, string suffix structures, strings

Strange LCS

bitmasks, dp, graphs, greedy, strings

Holiday Wall Ornaments

dp, strings

Rescue Niwen!

dp, greedy, string suffix structures, strings

Stringforces

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

Erase and Extend (Hard Version)

binary search, data structures, greedy, hashing, string suffix structures, strings, two pointers

Omkar and Akmar

chinese remainder theorem, combinatorics, constructive algorithms, fft, games, geometry, math, meet-in-the-middle, string suffix structures

String Distance

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

Kill Anton

brute force, constructive algorithms, data structures, math, strings

Chainword

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

Chaotic Merge

combinatorics, dp, math, strings

Enormous XOR

bitmasks, constructive algorithms, greedy, math, strings, two pointers

Exam

data structures, string suffix structures, trees

Pattern Matching

bitmasks, data structures, dfs and similar, graphs, hashing, sortings, strings

A Bit Similar

bitmasks, brute force, hashing, string suffix structures, strings, two pointers

Song of the Sirens

combinatorics, divide and conquer, hashing, math, string suffix structures, strings

Death DBMS

data structures, string suffix structures, strings, trees

Cyclic Shifts

*special problem, strings

Minlexes

dp, greedy, implementation, strings

Poman Numbers

bitmasks, greedy, math, strings

x-prime Substrings

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

Boboniu and Banknote Collection

strings

Twilight and Ancient Scroll (harder version)

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

Twilight and Ancient Scroll (easier version)

dp, hashing, implementation, string suffix structures, strings

Viruses

*special problem, dp, shortest paths, string suffix structures

Construct the String

data structures, dp, strings

Rotating Substrings

dp, strings

Kaavi and Magic Spell

dp, strings

Letters and Question Marks

bitmasks, dp, string suffix structures

Reachable Strings

data structures, hashing, strings

Concatenation with intersection

data structures, hashing, strings, two pointers

Au Pont Rouge

binary search, dp, strings

Erase Subsequences

dp, strings

Fedya the Potter Strikes Back

data structures, strings

Enchanted Artifact

constructive algorithms, interactive, strings

Asterisk Substrings

string suffix structures

Two Bracket Sequences

dp, strings, two pointers

Awesome Substrings

math, strings

Permutation Concatenation

string suffix structures

Find String in a Grid

data structures, dp, strings, trees

Middle-Out

constructive algorithms, greedy, strings

kotlinkotlinkotlinkotlin...

*special problem, graphs, implementation, strings

Koala and Notebook

data structures, dfs and similar, graphs, shortest paths, strings, trees

Indie Album

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

Expected Value Again

combinatorics, strings

You Are Given Some Strings...

brute force, string suffix structures, strings

The minimal unique substring

constructive algorithms, math, strings

Three Religions

dp, implementation, strings

String Multiplication

dp, greedy, strings

Morse Code

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

Modest Substrings

dp, strings

Ж-function

string suffix structures, strings

Mateusz and an Infinite Sequence

bitmasks, brute force, dp, strings

Two Prefixes

strings

Vasya and Templates

greedy, implementation, strings

Speed Dial

dp, strings, trees

Palindromic Magic

data structures, hashing, strings

Sonya and Matrix Beauty

strings

Yet Another LCP Problem

data structures, string suffix structures

Fibonacci Suffix

strings

Side Transmutations

combinatorics, strings

String Journey

data structures, dp, string suffix structures

Detect Robots

data structures, strings

Tree and XOR

strings, trees

Refactoring

greedy, implementation, strings

Vasya and Big Integers

binary search, data structures, dp, hashing, strings

Moonwalk challenge

data structures, strings, trees

Speckled Band

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