A Trance of Nightfall

dp, geometry, matrices, probabilities

Rain and Umbrellas

dp

Three displays

brute force, dp, implementation

Pencils and Boxes

binary search, data structures, dp, greedy, two pointers

Elevator

dp, graphs, shortest paths

XOR-pyramid

dp

Cut 'em all!

dfs and similar, dp, graphs, greedy, trees

K Paths

combinatorics, data structures, dp, fft, math

Addition on Segments

bitmasks, data structures, divide and conquer, dp

Bookshelves

bitmasks, dp, greedy

Cactus to Tree

dp, graphs, trees

Perfect Groups

dp, math, number theory

Kuro and Topological Parity

dp

Kuro and GCD and XOR and SUM

binary search, bitmasks, brute force, data structures, dp, dsu, greedy, math, number theory, strings, trees

Consecutive Subsequence

dp

Short Code

data structures, dp, greedy, strings, trees

Destruction of a Tree

constructive algorithms, dfs and similar, dp, greedy, trees

Lecture Sleep

data structures, dp, implementation, two pointers

Bandit Blues

combinatorics, dp, fft, math

Pathwalks

data structures, dp, graphs

Alternating Tree

combinatorics, dfs and similar, divide and conquer, dp, probabilities, trees

Mahmoud and Ehab and yet another xor task

bitmasks, dp, math, matrices

Mahmoud and Ehab and the xor-MST

bitmasks, dp, graphs, implementation, math

Guard Duty (medium)

binary search, dp, greedy, sortings

Encryption (hard)

data structures, dp

Encryption (medium)

dp

Heaps

dp, trees

Path Counting

combinatorics, dp

Runner's Problem

dp, matrices, sortings

Almost Increasing Array

data structures, dp

Fibonacci String Subsequences

combinatorics, dp, matrices

Timetable

dp

Cashback

data structures, dp, greedy, math

Our Tanya is Crying Out Loud

dp, greedy

Cutlet

data structures, dp

Erasing Substrings

bitmasks, dp, greedy

World of Tank

dp, greedy

Sleepy Game

dfs and similar, dp, games, graphs

Fafa and Ancient Mathematics

dfs and similar, dp, trees

A Preponderant Reunion

constructive algorithms, dp

A Twisty Movement

dp

Palindrome Partition

dp, string suffix structures, strings

Escape Through Leaf

data structures, dp, geometry

Team Work

combinatorics, dp, math

Tree

binary search, dp, trees

Coins Exhibition

data structures, dp, math

Teodor is not a liar!

data structures, dp

Chat

*special problem, dp

Minimal Subset Difference

dp

Wardrobe

dp, greedy

Riverside Curio

data structures, dp, greedy

Divisibility

constructive algorithms, dp, greedy, number theory

Birds

dp

Tanks

dp, greedy, implementation

Substring

dfs and similar, dp, graphs

Perfect Number

binary search, brute force, dp, implementation, number theory

Stranger Trees

dp, math, matrices, trees

Pollywog

combinatorics, dp, matrices

MADMAX

dfs and similar, dp, games, graphs

The Monster

dp, greedy, implementation, math

Permute Digits

dp, greedy

Ember and Storm's Tree Game

combinatorics, dp, games, trees

Sum the Fibonacci

bitmasks, divide and conquer, dp, fft, math

Travelling Salesman and Special Numbers

brute force, combinatorics, dp

Strongly Connected Tournament

dp, graphs, math, probabilities

Logical Expression

bitmasks, dp, shortest paths

Party Lemonade

bitmasks, dp, greedy

The Way to Home

dfs and similar, dp, greedy, implementation

Coprocessor

dfs and similar, dp, graphs, greedy

Python Indentation

dp

New Year and Original Order

dp, math

New Year and Entity Enumeration

bitmasks, combinatorics, dp, math

New Year and Arbitrary Arrangement

dp, math, probabilities

Reverses

dp, string suffix structures, strings

Party

bitmasks, brute force, dp, graphs

Clear The Matrix

bitmasks, dp

Maximum Questions

data structures, dp, strings

Unusual Sequences

bitmasks, combinatorics, dp, math, number theory

Square Subsets

bitmasks, combinatorics, dp, math

Ralph and Mushrooms

dp, graphs

QAQ

brute force, dp

Counting Arrays

combinatorics, dp, math, number theory

Credit Card

data structures, dp, greedy, implementation

Sloth

dfs and similar, dp, graph matchings, trees

Pride

brute force, dp, greedy, math, number theory

Mod Mod Mod

binary search, dp, math

Connecting Vertices

dp, graphs

Almost Identity Permutations

combinatorics, dp, math

Maximum Element

combinatorics, dp, math

Photo Processing

binary search, dp

Packmen Strike Back

binary search, dp, math

Numbers on the blackboard

combinatorics, dp

Nikita and string

brute force, dp

Delivery Club

binary search, data structures, dp

Awards For Contestants

brute force, data structures, dp

Balanced Substring

dp, implementation

Maximum splitting

dp, greedy, math, number theory

The Intriguing Obsession

combinatorics, dp, math

Yet Another Minimization Problem

divide and conquer, dp

Policeman and a Tree

dp, graphs, trees