Skyscrapers (easy version)

brute force, data structures, dp, greedy

Uniqueness

binary search, brute force, implementation, two pointers

Nikita and string

brute force, dp

The Humanoid

brute force, dp, sortings

Orray

bitmasks, brute force, greedy, math, sortings

Line Empire

binary search, brute force, dp, greedy, implementation, math

Pride

brute force, dp, greedy, math, number theory

Hyperset

brute force, data structures, implementation

Vasya and Multisets

brute force, dp, greedy, implementation, math

Arpa’s obvious problem and Mehrdad’s terrible solution

brute force, math, number theory

Modulo Equality

brute force, sortings

A + B Strikes Back

*special problem, brute force, constructive algorithms, dsu, implementation

Almost Arithmetic Progression

brute force, implementation, math

Marvolo Gaunt's Ring

brute force, data structures, dp

Balance (Easy version)

brute force, data structures, implementation, number theory

Convert to Ones

brute force, greedy, implementation, math

Bear and Three Musketeers

brute force, dfs and similar, graphs, hashing

Kayaking

brute force, greedy, sortings

Removing Columns

brute force, constructive algorithms, implementation

Link/Cut Tree

brute force, implementation

New Year and Curling

brute force, geometry, implementation, math

Fire Again

brute force, dfs and similar, shortest paths

Photo of The Sky

brute force, implementation, math, sortings

Coach

brute force, dfs and similar, graphs

Lorenzo Von Matterhorn

brute force, data structures, implementation, trees

Dasha and Password

brute force, dp, implementation

Secret Combination

brute force, constructive algorithms, implementation

Triangle

brute force, geometry

Searching for Graph

brute force, constructive algorithms, graphs

Vasya and Robot

brute force, greedy, math

Almost Arithmetical Progression

brute force, dp

Qualification Rounds

bitmasks, brute force, constructive algorithms, dp

Palindrome pairs

*special problem, brute force, dp, strings

Curriculum Vitae

brute force, implementation

Bargaining Table

brute force, dp

Xenia and Spies

brute force, greedy, implementation

Batch Sort

brute force, greedy, implementation, math

Kolya and Tandem Repeat

brute force, implementation, strings

Two Seals

brute force, implementation

Sereja and Swaps

brute force, sortings

Which floor?

brute force, implementation

Dima and Text Messages

brute force, strings

Jeopardy of Dropped Balls

binary search, brute force, dsu, implementation

BerOS File Suggestion

brute force, implementation

PFAST Inc.

bitmasks, brute force, graphs

Shifts

brute force, two pointers

New Problem

brute force, strings

Solution for Cube

brute force, implementation

Party

brute force, dfs and similar, dsu, graphs

Jury Size

brute force, implementation

Charming Meals

binary search, brute force, greedy, sortings

Summer Homework

brute force, data structures

EKG

brute force, dfs and similar

Easy Tape Programming

brute force, implementation

Hamburgers

binary search, brute force

Circle of Monsters

brute force, constructive algorithms, greedy, math

Array Walk

brute force, dp, greedy

Maximum Sum of Products

brute force, dp, implementation, math, two pointers

Kuroni and Impossible Calculation

brute force, combinatorics, math, number theory

Boboniu and Bit Operations

bitmasks, brute force, dp, greedy

Ehab and Prefix MEXs

brute force, constructive algorithms, greedy

Set or Decrease

binary search, brute force, greedy, sortings

Erase and Extend (Easy Version)

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

Strange Test

binary search, bitmasks, brute force, dp, math

Another Problem on Strings

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

Partitioning the Array

brute force, math, number theory

Say No to Palindromes

brute force, constructive algorithms, dp, strings

Gardener and Tree

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

Fence Painting

brute force, constructive algorithms, greedy

Equalizing by Division (hard version)

brute force, math, sortings

Min Cost String

brute force, constructive algorithms, graphs, greedy, strings

To Become Max

binary search, brute force, data structures, dp

Tracking Segments

binary search, brute force, data structures, two pointers

Dima and a Bad XOR

bitmasks, brute force, constructive algorithms, dp

Zero-Sum Prefixes

brute force, data structures, dp, greedy, implementation

Gerald's Hexagon

brute force, geometry, math

Counting Rectangles

brute force, data structures, dp, implementation

Permutation by Sum

brute force, greedy, math

Good Key, Bad Key

bitmasks, brute force, dp, greedy, math

The Enchanted Forest

brute force, greedy

Binary String Copying

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

Remove Adjacent

brute force, constructive algorithms, greedy, strings

Watering an Array

brute force, greedy, implementation, math

Playlist

brute force, data structures, sortings

Welfare State

binary search, brute force, data structures, sortings

Colorful Graph

brute force, dfs and similar, graphs

Planar Reflections

brute force, data structures, dp

Basic Diplomacy

brute force, constructive algorithms, greedy, implementation

Thor

brute force, data structures, implementation

Divide and Summarize

binary search, brute force, data structures, divide and conquer, implementation, sortings

Eat the Chip

brute force, games, greedy, math

Good Triples

brute force, combinatorics, number theory

p-binary

bitmasks, brute force, math

Color with Occurrences

brute force, data structures, dp, greedy, strings

Compression and Expansion

brute force, data structures, greedy, implementation, trees

Mind Control

brute force, data structures, implementation

Maximum Product Strikes Back

brute force, implementation, math, two pointers

Tokitsukaze and Strange Inequality

brute force, data structures, dp

Menorah

brute force, graphs, greedy, math

Weakened Common Divisor

brute force, greedy, number theory