Permutation Oddness

combinatorics, dp, math

Power Boxes

constructive algorithms, dp, implementation, interactive

Sliding Tree

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

Flint and Steel

data structures, dp, graphs

I Yearned For The Mines

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

Chicken Jockey

dp, greedy

Famous Choreographer

hashing, implementation, strings

Rada and the Chamomile Valley

dfs and similar, graphs, shortest paths

Arithmetics Competition

binary search, data structures, greedy, sortings, ternary search

From 1 to Infinity

binary search, dp, implementation, math

Sea, You & copriMe

brute force, constructive algorithms, graphs, greedy, math, number theory

Wafu!

bitmasks, brute force, data structures, dfs and similar, dp, math

Unjust Binary Life

binary search, data structures, greedy, greedy, math, sortings, two pointers

Top-K Tracker (Hard Version)

interactive, interactive

Top-K Tracker (Easy Version)

interactive

Induced Subgraph Queries

data structures, graphs, sortings

Permutation Blackhole

brute force, combinatorics, dp, implementation, math

Interactive RBS (Hard Version)

binary search, bitmasks, constructive algorithms, dp, interactive

Interactive RBS (Medium Version)

binary search, bitmasks, constructive algorithms, interactive

Interactive RBS (Easy Version)

binary search, bitmasks, constructive algorithms, interactive

Stay or Mirror

brute force, data structures, dp, greedy, sortings

Strict Triangle

graphs, greedy, shortest paths

Submedians (Hard Version)

binary search, constructive algorithms, data structures, math, two pointers

Submedians (Easy Version)

binary search, data structures, dp, greedy, math

Sum of LDS

brute force, combinatorics, dp, greedy, math

23 Rises Again

brute force, dfs and similar, dp, flows, graph matchings, graphs, greedy, implementation, probabilities, trees

Inter Active (Hard Version)

binary search, bitmasks, constructive algorithms, graphs, implementation, interactive, math, probabilities

Inter Active (Easy Version)

binary search, constructive algorithms, interactive, probabilities

Hamed and AghaBalaSar

brute force, combinatorics, dp, math, probabilities

Ancient Tree

constructive algorithms, data structures, dfs and similar, dsu, greedy, trees

Root was Built by Love, Broken by Destiny

combinatorics, dfs and similar, graphs, trees

Big Wins! (hard version)

binary search, data structures, divide and conquer, dsu, trees, two pointers

Big Wins! (easy version)

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

1-1-1, Free Tree!

brute force, data structures, dfs and similar, graphs, implementation, trees

Timofey and Docker

binary search, divide and conquer, dp

Sets of Complementary Sums

brute force, combinatorics, dp, math, two pointers

Segments Covering

dp, math, probabilities

Lexicographic Partition

constructive algorithms, math, trees

Longest Good Subsequence

dp, math, trees

Maximise Sum

binary search, data structures

Appending Permutations (Hard Version)

combinatorics, dp

Appending Permutations (Easy Version)

combinatorics, dp

Make it Zero

constructive algorithms, greedy, math

Make a Palindrome

greedy, sortings, two pointers

Modular Sorting

brute force, data structures, greedy, math, number theory, sortings

Minimize Fixed Points

constructive algorithms, number theory

Tree Parking

combinatorics, fft, math, trees

Colorful Polygon

constructive algorithms, divide and conquer, geometry

Greedy Grid Counting

combinatorics, dp, greedy, math

Traffic Lights

brute force, data structures, divide and conquer, dp, graphs, greedy, shortest paths

Manhattan Pairs

constructive algorithms, geometry, greedy, math, sortings

Ice Baby

binary search, brute force, data structures, dp, implementation, sortings

Gangsta

data structures, divide and conquer, math, sortings

Yamakasi

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

Eulerian Line Graph

graphs, greedy, math

Superb Graphs

2-sat, graphs

Lanes of Cars

binary search, dp, ternary search

Matrix game

combinatorics, math

Volcanic Eruptions

dfs and similar, dp, greedy, shortest paths, trees

And Constraint

bitmasks, dp, greedy

Token Removing

combinatorics, dp, math

Shifts and Swaps

data structures, graphs, hashing, trees

Grid Coloring

constructive algorithms, geometry, greedy, math

Red Light, Green Light (Hard version)

binary search, brute force, data structures, dfs and similar, dp, graphs, implementation, math, number theory

Red Light, Green Light (Easy version)

brute force, dfs and similar, dp, graphs, implementation, number theory

Incessant Rain

data structures, divide and conquer, sortings

Omg Graph

brute force, dsu, graphs, greedy, shortest paths, sortings

Wildflower

combinatorics, dfs and similar, trees

Lost Soul

brute force, greedy

Gellyfish and Lycoris Radiata (Hard Version)

data structures

Gellyfish and Lycoris Radiata (Easy Version)

data structures

Gellyfish and Mayflower

dp, graphs

Gellyfish and Forget-Me-Not

bitmasks, dp, games, greedy, math

Gellyfish and Eternal Violet

combinatorics, dp, greedy, math, probabilities

Gellyfish and Camellia Japonica

brute force, constructive algorithms, dfs and similar, dp, graphs, greedy, trees

Build an Array

brute force, constructive algorithms, dp, greedy, math, number theory

Small Operations

binary search, brute force, dfs and similar, dp, math, number theory, sortings

Two Arrays

constructive algorithms, dfs and similar, graphs, math

From Kazan with Love

dfs and similar, graphs, implementation, trees

Cheater

binary search, constructive algorithms, greedy, implementation

Smilo and Minecraft

brute force, constructive algorithms, greedy

Variables and Operations

graphs, greedy, shortest paths

Tree Colorings

combinatorics, dfs and similar, dp, graphs, math, number theory, trees

Reachability and Tree

constructive algorithms, dfs and similar, graphs, trees

Divisible Subarrays

binary search, bitmasks, brute force, data structures, interactive

Puzzle

brute force, constructive algorithms, greedy, math

Changing the String

binary search, data structures, greedy, implementation, sortings, strings

Faculty

brute force, greedy, math, number theory

Melody

dfs and similar, graphs, implementation

Fewer Batteries

binary search, dfs and similar, dp, graphs, greedy, hashing

Penguin Steps

binary search, dfs and similar, flows, graphs, shortest paths

Binary String Wowee

combinatorics, dp, strings

D/D/D

dfs and similar, graphs, greedy, shortest paths

Hacking Numbers (Hard Version)

constructive algorithms, interactive, math, number theory

Hacking Numbers (Medium Version)

constructive algorithms, interactive, math, number theory

Fallen Towers

binary search, greedy

Spruce Dispute

constructive algorithms, dfs and similar, graphs, greedy, implementation, shortest paths, trees

Needle in a Numstack

binary search, brute force, implementation, interactive

Cycling (Hard Version)

binary search, brute force, data structures, dp, greedy

Cycling (Easy Version)

binary search, brute force, dp, greedy