Changing Volume

math

Send Tree to Charlie

combinatorics, dfs and similar, dsu, trees

Tree Queries

data structures, probabilities, trees

Point Ordering

constructive algorithms, geometry, interactive, math

Send Boxes to Alice (Hard Version)

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

Send Boxes to Alice (Easy Version)

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

Feeding Chicken

constructive algorithms, greedy, implementation

Cheap Robot

binary search, dsu, graphs, shortest paths, trees

Antenna Coverage

data structures, dp, greedy, sortings

Harmonious Graph

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

Sweets Eating

dp, greedy, math, sortings

Silly Mistake

greedy, implementation

Single Push

implementation

Road Construction

flows, graphs

Addition Robot

data structures, math, matrices

Tiling Terrace

brute force, dp

Mission Possible

Twin Buildings

greedy, implementation

Performance Review

data structures

Regular Forestation

hashing, trees

Songwriter

greedy, two pointers

Find String in a Grid

data structures, dp, strings, trees

Even Path

data structures, implementation

Cleaning Robots

dp, trees

Copying Homework

Red-White Fence

combinatorics, fft

Voting (Hard Version)

binary search, data structures, greedy

Voting (Easy Version)

data structures, dp, greedy

Salary Changing

binary search, greedy, sortings

Minimize The Integer

greedy, two pointers

Binary Palindromes

greedy, strings

Broken Keyboard

brute force, strings, two pointers

Wires

dfs and similar, graphs, greedy

SmartGarden

constructive algorithms, divide and conquer

Divide The Students

binary search, greedy, math

Projectors

flows, graphs

The Parade

binary search, greedy

Show Must Go On

binary search, brute force, greedy, shortest paths

Happy Birthday

math

Discarding Game

dp, greedy, two pointers

Data Center

brute force, implementation

The Coronation

graphs, implementation

Conference Problem

dp

Trip to Saint Petersburg

data structures

The Feast and the Bus

brute force, constructive algorithms, greedy, math

Berstagram

implementation

Maximum Weight Subset

dp, trees

By Elevator or Stairs?

dp, shortest paths

Too Many Segments (hard version)

data structures, greedy, sortings

Too Many Segments (easy version)

greedy

Good Numbers (hard version)

binary search, greedy, math, meet-in-the-middle

Good Numbers (easy version)

brute force, greedy, implementation

Books Exchange (hard version)

dfs and similar, dsu, math

Books Exchange (easy version)

dsu, math

Yet Another Dividing into Teams

math

The World Is Just a Programming Task (Easy Version)

brute force, dp, greedy, implementation

Grow The Tree

greedy, math, sortings

Integer Points

geometry, math

Cursor Distance

Daniel and Spring Cleaning

bitmasks, brute force, combinatorics, dp

Hyakugoku and Ladders

dp, probabilities, shortest paths

Shichikuji and Power Grid

dsu, graphs, greedy, shortest paths, trees

Constanze's Machine

dp

Restricted RPS

constructive algorithms, dp, greedy

Good ol' Numbers Coloring

math, number theory

Running in Pairs

constructive algorithms, greedy, math

Chips

constructive algorithms, implementation

Minimizing Difference

binary search, constructive algorithms, greedy, sortings, ternary search, two pointers

Paint the Tree

brute force, constructive algorithms, dp, graphs, implementation, trees

The Football Season

brute force, math, number theory

Rooms and Staircases

brute force, implementation

Pens and Pencils

math

Character Swap (Hard Version)

strings

Character Swap (Easy Version)

strings

Maximum Square

implementation

Planar Perimeter

constructive algorithms, graphs

Number Discovery

math

Sum Balance

bitmasks, dfs and similar, dp, graphs

0-1 MST

dfs and similar, dsu, graphs, sortings

Tile Painting

constructive algorithms, math, number theory

Football

graphs

Swiper, no swiping!

graphs, implementation

Turtle

dp, implementation

Catowice City

2-sat, dfs and similar, graph matchings, graphs

Queue in the Train

data structures, greedy, implementation

The World Is Just a Programming Task (Hard Version)

implementation

Ivan the Fool and the Probability Theory

combinatorics, dp, math

Adilbek and the Watering System

data structures, greedy, sortings

The Maximum Subtree

dfs and similar, dp, graphs, trees

Keyboard Purchase

bitmasks, dp

AB-string

binary search, combinatorics, dp, strings

Standard Free2play

dp, greedy, math

Kill `Em All

greedy, sortings

Prime Subtraction

math, number theory

Balanced Reversals

constructive algorithms

Balanced Distribution

data structures, dp, greedy

Balanced Domino Placements

combinatorics, dp

Balanced Binary Search Trees

dp, math

Balanced Playlist

binary search, data structures, implementation

Balanced Removals (Harder)

binary search, constructive algorithms, divide and conquer, greedy, implementation, sortings