Two Strings Swaps

implementation

Berland and the Shortest Paths

brute force, dfs and similar, graphs, shortest paths

Median on Segments (General Case Edition)

sortings

Median on Segments (Permutations Edition)

sortings

Polycarp and Div 3

dp, greedy, number theory

Sonya and Bitwise OR

bitmasks, data structures, divide and conquer

Sonya and Ice Cream

binary search, data structures, dp, greedy, shortest paths, trees

Sonya and Matrix

brute force, constructive algorithms, implementation

Sonya and Robots

constructive algorithms, implementation

Abbreviation

dp, hashing, strings

Tree Constructing

constructive algorithms, graphs

Coins and Queries

greedy

Another array reconstruction algorithm

Bernstein-Vazirani algorithm

Oracle for majority function

Distinguish zero state and plus state without errors

Distinguish zero state and plus state with minimum error

Distinguish four 2-qubit states - 2

Distinguish four 2-qubit states

Distinguish GHZ state and W state

Generate W state

Generate superposition of two basis states

Deutsch-Jozsa algorithm

*special problem

Oracle for f(x) = k-th element of x

*special problem

Distinguish Bell states

*special problem

Distinguish plus state and minus state

*special problem

Generate GHZ state

*special problem

Generate Bell state

*special problem

Two-Paths

data structures, dp, trees

One Occurrence

data structures, divide and conquer

We Need More Bosses

dfs and similar, graphs, trees

Yet Another Problem On a Subsequence

combinatorics, dp

Covered Points Count

data structures, implementation, sortings

Light It Up

greedy

Cards and Joy

dp

Reachability from the Capital

dfs and similar, graphs, greedy

Equalize the Remainders

data structures, greedy, implementation

Good Subsegments

data structures

Cycles in product

combinatorics, divide and conquer, trees

Sky Full of Stars

combinatorics, math

Roman Digits

brute force, combinatorics, dp, greedy, math

Convert to Ones

brute force, greedy, implementation, math

Cowmpany Cowmpensation

combinatorics, dp, math, trees

Number Clicker

divide and conquer, graphs, meet-in-the-middle, number theory

Game

math

Leaving the Bar

brute force, data structures, geometry, greedy, math, sortings

Suit and Tie

greedy, implementation, math

Tesla

constructive algorithms, implementation

Knights of a Polygonal Table

greedy, implementation, sortings

The Moral Dilemma

Nikita and Order Statistics

chinese remainder theorem, fft, math

Compute Power

binary search, dp, greedy

Careful Maneuvering

bitmasks, brute force, geometry

Open Communication

bitmasks, brute force

Two Squares

geometry, implementation

Nastya and King-Shamans

binary search, data structures

Nastya and a Game

brute force, implementation, math

Nastya and a Wardrobe

math

Nastya Studies Informatics

math, number theory

Concise and clear

brute force, greedy, implementation, math

Bus Number

brute force, combinatorics, math

Bishwock

dp, greedy

Candies

binary search, implementation

GCD Counting

divide and conquer, dp, dsu, number theory, trees

Flow Control

dfs and similar, dp, greedy, trees

Post Lamps

brute force, greedy

Graph And Its Complement

constructive algorithms, graphs, implementation

Bracket Sequences Concatenation Problem

implementation

A Trance of Nightfall

dp, geometry, matrices, probabilities

A Shade of Moonlight

binary search, geometry, math, sortings, two pointers

A Mist of Florescence

constructive algorithms, graphs

Rain and Umbrellas

dp

Divisibility by 25

brute force, greedy

Points and Powers of Two

brute force, math

Equal Sums

implementation, sortings

Three displays

brute force, dp, implementation

Oppa Funcan Style Remastered

graphs, math, number theory, shortest paths

Prince's Problem

brute force, data structures, math, number theory, trees

Perfect Encoding

fft, math

AND Graph

bitmasks, dfs and similar, dsu, graphs

Petr and Permutations

combinatorics, math

Fair

graphs, greedy, number theory, shortest paths

Team Players

combinatorics

Isomorphic Strings

hashing, strings

Pencils and Boxes

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

Sand Fortress

binary search, constructive algorithms, math

Liebig's Barrels

greedy

NN country

binary search, data structures, trees

Arkady and Rectangles

data structures

Elevator

dp, graphs, shortest paths

XOR-pyramid

dp

Finite or not?

implementation, math

The Meeting Place Cannot Be Changed

dfs and similar, graphs

Billiard

geometry, number theory

Shark

brute force, data structures, dsu, trees

Cut 'em all!

dfs and similar, dp, graphs, greedy, trees

K Paths

combinatorics, data structures, dp, fft, math

Magic multisets

data structures

Round Marriage

binary search, graph matchings, greedy

Addition on Segments

bitmasks, data structures, divide and conquer, dp