Passports

dp, implementation

Cycle sort

dsu, math

AB-Strings

constructive algorithms, strings

Hills

dp

Chemical table

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

Photo of The Sky

brute force, implementation, math, sortings

Planning The Expedition

binary search, brute force, implementation

Stages

greedy, implementation, sortings

Tree

fft, graphs, trees

Store

data structures

Mars rover

dfs and similar, graphs, implementation, trees

Border

number theory

Rocket

binary search, interactive

Fly

binary search, math

Allowed Letters

bitmasks, flows, graph matchings, graphs, greedy

Dominant Indices

data structures, dsu, trees

Intercity Travelling

combinatorics, math, probabilities

Relatively Prime Graph

brute force, constructive algorithms, graphs, greedy, math

Annoying Present

greedy, math

Minimum Ternary String

greedy, implementation

Game Shopping

implementation

Turn the Rectangles

greedy, sortings

Romaji

implementation, strings

Mini Metro

dp

Ants

2-sat, data structures, trees

Guess two numbers

binary search, interactive

Pave the Parallelepiped

bitmasks, brute force, combinatorics, math, number theory

Reorder the Array

combinatorics, data structures, math, sortings, two pointers

Xor-Paths

bitmasks, brute force, dp, meet-in-the-middle

Military Problem

dfs and similar, graphs, trees

Two Strings Swaps

implementation

Three Parts of the Array

binary search, data structures, two pointers

Polycarp's Practice

greedy, implementation, sortings

Adjacent Replacements

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

Summarize to the Power of Two

brute force, greedy, implementation

Delete from the Left

brute force, implementation, strings

Tanya and Stairways

implementation

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

Sonya and Exhibition

constructive algorithms, greedy, implementation, math

Sonya and Hotels

implementation

Abbreviation

dp, hashing, strings

Tree Constructing

constructive algorithms, graphs

Coins and Queries

greedy

Intense Heat

brute force, implementation, math

Binary String Constructing

constructive algorithms

Polycarp's Pockets

implementation

Another array reconstruction algorithm

Bernstein-Vazirani algorithm

Oracle for majority function

Oracle for f(x) = b * x + (1 - b) * (1 - x) mod 2

Oracle for f(x) = b * x mod 2

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

Distinguish zero state and W state

Generate W state

Generate superposition of two basis states

Generate superposition of zero state and a basis state

Generate superposition of all basis states

Deutsch-Jozsa algorithm

*special problem

Oracle for f(x) = parity of the number of 1s in x

*special problem

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

*special problem

Distinguish multi-qubit basis states

*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

Generate plus state or minus 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

Codehorses T-shirts

greedy, implementation

Cards and Joy

dp

Reachability from the Capital

dfs and similar, graphs, greedy

Equalize the Remainders

data structures, greedy, implementation

Alphabetic Removals

implementation

Reversing Encryption

implementation

Mishka and Contest

brute force, implementation

Cutting

dp, greedy, sortings

Balloons

constructive algorithms, 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

World Cup

binary search, math

Hit the Lottery

dp, greedy

Cowmpany Cowmpensation

combinatorics, dp, math, trees