Railway System

constructive algorithms, graphs, greedy, interactive, sortings

Fish Weight

constructive algorithms, greedy

High Load

constructive algorithms, greedy, implementation, trees

Money Transfers

constructive algorithms, data structures, greedy, sortings

Three Logos

bitmasks, brute force, constructive algorithms, geometry, implementation, math

Decreasing Debts

constructive algorithms, data structures, graphs, greedy, implementation, math, two pointers

Tokitsukaze and Two Colorful Tapes

constructive algorithms, dfs and similar, graphs, greedy

Lazy Student

constructive algorithms, data structures, graphs

Unshuffling a Deck

constructive algorithms, implementation

Three Sequences

constructive algorithms, data structures, greedy, math

Amity Assessment

brute force, constructive algorithms, implementation

Make It Increasing

binary search, constructive algorithms, data structures, dp, implementation

Permutation Addicts

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

Once Again...

constructive algorithms, dp, matrices

Epidemic in Monstropolis

constructive algorithms, dp, greedy, two pointers

Constructing Tests

binary search, brute force, constructive algorithms

Equal Tree Sums

constructive algorithms, dfs and similar, math, trees

GCD Queries

constructive algorithms, interactive, number theory

Bottle Arrangements

constructive algorithms

Matching vs Independent Set

constructive algorithms, graphs, greedy, sortings

Rebus

constructive algorithms, expression parsing, greedy, math

Regular Bridge

constructive algorithms, graphs, implementation

Omkar and Duck

bitmasks, constructive algorithms, interactive, math

Permutation Shift

brute force, combinatorics, constructive algorithms, dfs and similar, dsu, graphs, math

Points on Plane

constructive algorithms, divide and conquer, geometry, greedy, sortings

Letter Exchange

constructive algorithms

Recover the String

constructive algorithms, greedy, implementation, math

Train Splitting

constructive algorithms, graphs, greedy

Party

constructive algorithms, graphs, math

Simple Subset

constructive algorithms, greedy, number theory

Game with modulo

binary search, constructive algorithms, interactive

Interacdive Problem

binary search, constructive algorithms, interactive

Circular Spanning Tree

constructive algorithms, implementation, trees

Nash Matrix

constructive algorithms, dfs and similar, graphs, implementation

Bear and Two Paths

constructive algorithms, graphs

Bottom-Tier Reversals

constructive algorithms, greedy

Decryption

constructive algorithms, implementation, math, number theory

Colored Rooks

constructive algorithms, graphs

Lucky Permutation

constructive algorithms, math

Triangular Paths

constructive algorithms, graphs, math, shortest paths, sortings

Island Puzzle

constructive algorithms, implementation

Grid Xor

constructive algorithms, greedy, implementation, interactive, math

Connect the Points

brute force, constructive algorithms, geometry

Terse princess

constructive algorithms, greedy

Equalizing Two Strings

constructive algorithms, sortings, strings

Build a Tree and That Is It

constructive algorithms, implementation, trees

Mahmoud and Ehab and another array construction task

constructive algorithms, greedy, math, number theory

Yaroslav and Sequence

constructive algorithms

Petya and His Friends

constructive algorithms, math, number theory

Four Segments

brute force, constructive algorithms, geometry, implementation, math

MEX vs DIFF

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

Merge Sort

constructive algorithms, divide and conquer

Bank Hacking

constructive algorithms, data structures, dp, trees

XOR Break --- Solo Version

bitmasks, constructive algorithms, greedy

Pavel and barbecue

constructive algorithms, dfs and similar

Clear Symmetry

constructive algorithms, dp, math

Array Shuffling

constructive algorithms, graphs, greedy

Perfect Triples

bitmasks, brute force, constructive algorithms, divide and conquer, math

Spanning Tree with One Fixed Degree

constructive algorithms, dfs and similar, dsu, graphs, greedy

Salyg1n and Array (hard version)

constructive algorithms, interactive

Send Boxes to Alice (Hard Version)

constructive algorithms, greedy, math, number theory, ternary search, two pointers

Balls and Boxes

constructive algorithms, greedy, implementation

Delete Them

constructive algorithms, implementation

Secret

constructive algorithms, implementation

Gluttony

constructive algorithms, greedy

Minimax

constructive algorithms, greedy, strings

Guess the K-th Zero (Hard version)

binary search, constructive algorithms, data structures, interactive

Kuroni and the Score Distribution

constructive algorithms, greedy, implementation, math

Lexicography

constructive algorithms, strings

Rudolph and Mimic

constructive algorithms, implementation, interactive

Little Artem and Dance

brute force, constructive algorithms, implementation

Treelabeling

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

Sum Graph

brute force, constructive algorithms, graphs, implementation, interactive, shortest paths, trees

Bitwise Queries (Hard Version)

bitmasks, constructive algorithms, interactive, math

Up the hill

constructive algorithms, implementation

Mahmoud and a xor trip

bitmasks, constructive algorithms, data structures, dfs and similar, dp, math, trees

Optimal Number Permutation

constructive algorithms

Rudolf and Subway

constructive algorithms, dfs and similar, graphs, shortest paths

Paired Payment

binary search, brute force, constructive algorithms, dp, flows, graphs, shortest paths

Harmony Analysis

constructive algorithms

Convex Shape

constructive algorithms, implementation

Dwarves, Hats and Extrasensory Abilities

binary search, constructive algorithms, geometry, interactive

Inversion SwapSort

constructive algorithms, greedy, sortings

Drazil and Tiles

constructive algorithms, greedy

Ehab and another another xor problem

bitmasks, constructive algorithms, implementation, interactive

Rectangular Congruence

constructive algorithms, number theory

Queue

constructive algorithms, dp

Sum of Digits

brute force, constructive algorithms, dp, greedy

Destruction of a Tree

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

Train Hard, Win Easy

constructive algorithms, greedy, math, sortings

Ability To Convert

constructive algorithms, dp, greedy, math, strings

Unordered Subsequence

constructive algorithms, greedy

Shovel Sale

constructive algorithms, math

Complete The Graph

binary search, constructive algorithms, graphs, shortest paths

No Palindromes

brute force, constructive algorithms, divide and conquer, greedy, hashing, implementation, math, strings

ConstructOR

bitmasks, chinese remainder theorem, combinatorics, constructive algorithms, math, number theory

Domino (hard version)

constructive algorithms, implementation, math

The LCMs Must be Large

bitmasks, brute force, constructive algorithms, math, number theory

Berland Beauty

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

Processing Queries

*special problem, constructive algorithms, data structures, two pointers