[Video Tutorial Series] Graph Theory: From Beginner to Intermediate - Dardev

I am planning to post all solutions of CSES graph series ; while also discussing the necessary theory involved.

Update: I reuploaded the first 12 videos with better audio quality . All audios are good now.

Here is the entire playlist: Graph Theory Introduction Part 1 :: Overview and Representations of Graph - YouTube

Intro part 1: Graph Theory Introduction Part 1 :: Overview and Representations of Graph - YouTube

Intro part 2: Graph Theory Introduction Part 2 :: DFS and BFS - YouTube

CSES 1: Counting Rooms(1192): Graph 01: Counting Rooms (CSES 1192) :: Graph Theory: Flood Fill, DFS on a Grid, CSES 01 - YouTube

CSES 2: Labyrinth(1193): Graph 06: Labyrinth:: BFS on a Grid (CSES Graph 02: 1193) - YouTube

CSES 3: Building Roads: Graph 02: Building Roads :: Min Cost to Connect Graph with Unweighted Edges. (CSES Graph 03: 1666) - YouTube

CSES 4: Message Route Graph 05: Message Route :: BFS in Undirected. Single Source Shortest Path. (CSES Graph 04: 1667) - YouTube

CSES 5: Building Teams: Graph 03: Building Teams :: Graph Theory: Bipartite Graph, 2 Color Problem, CSES Graphs 05: 1668 - YouTube

CSES 6: Round Trip: Graph 04: Round Trip :: Cycle Retrieval, Cycle Detection, Undirected Graph, CSES 06: 1669 - YouTube

CSES 7: Monsters: Graph 07: Monsters :: Lava Flow, Multi-source BFS, BFS on a Grid (CSES 07: 1194) - YouTube

Theory Time: Heaps Part 1 — Intro to Heaps, Trees, Rooting a Tree, Binary Tree, Complete Binary Tree Graph 8.1: Heaps 1:: Intro to Heaps, Trees, Rooting a Tree, Binary Tree, Complete Binary Tree - YouTube

Theory Time: Heaps Part 2 — Inserting, Retrieving, Heapfication into Heap Graph 8.2: Heaps 2:: Inserting into, Retrieving from a Binary Min Heap. Heapfication. - YouTube

Theory Time: Heaps Part 3 — Flattening Heap into Vector. Navigating a Flattened Tree Graph 8.3: Heaps 3:: Flattening Heap into Vector. Navigating a Flattened Tree - YouTube

CSES 8: Shortest Routes I: 09 Graph Theory:: Dijkstra's Algorithm with CSES 08 Shortest Routes I (1671) - YouTube

CSES 9: Shortest Routes II: 11 Graph Theory:: Floyd Warshalls with CSES 9 Shortest Routes II (1672) All Source Shortest Paths - YouTube

CSES 10: High Score: 10 Graph Theory:: Bellman Ford's Algorithm with CSES 10 High Score (1673) - YouTube

CSES 11: Flight Discount: 12 Graph Theory:: Dijkstras with CSES 11 Flight Discount (1195) Single Source Shortest Path Modified - YouTube

CSES 12: Cycle Finding: 14 Graph Theory:: Bellman-Ford with CSES 12 Cycle Finding (1197) Retrieve Negative Cycle - YouTube

CSES 13: Flight Routes: 13 Graph Theory:: Dijkstras with CSES 13 Flight Routes (1196) Single Source Shortest PathS Modified - YouTube

CSES 14: Round Trip II: 15 Graph Theory:: DFS with Stack to Retrieve Cycle in Directed Graph CSES Round Trip II 1678 - YouTube

CSES 15: Course Schedule: 16 Graph Theory:: Topological Sort with CSES: Course Schedule 1679 - YouTube

CSES 16: Longest Flight Route: Graph 17: Longest Flight Route :: Modified Dijkstras(CSES 16: 1680) - YouTube

CSES 17: Game Routes: Graph 19: Game Routes:: Topological Sorting(CSES 17: 1681) - YouTube

CSES 18: Investigation: Graph 18: Investigation:: Modified Dijkstras(CSES 18: 1202) - YouTube

CSES 19: Planet Queries I

Planet Queries II

Very underrated. Your explanations are amazing!

I liked how you submitted your single source BFS code to prove that it won’t work.

Thanks! I am glad you are following the series.

Here are the updates:

I solved another CSES problem: Lava Flow and Multisource BFS - YouTube

Introduction to Trees, Binary Trees, Min/Max Heaps, Flattening a Tree into a Vector - YouTube

I made an introductory video 00 to make things even simpler - YouTube

I am reuploading the solution to the first problem, for greater audio clarity and better explanation/presentation - YouTube

Today I will try and share Dijkstra theory while solving the next CSES problem.

Language dependent or independent videos ?

I explain concepts in English. But my implementation is in C++, I explain every critical aspect of code though. Just check it out, you’ll like it.

This video series is really helpful! I am really excited about this series and will keep posting updates to support you. I just finished the first two videos. Nice explanation of BFS and DFS on the grid.

Thanks a lot for you effort and hard work. It is really helpful for the coding comminity.

Thank you guys. Please subscribe! Its a humble request . Will post more videos soon.

Hey please try to make a few more videos on Dijkstra algo, with some interesting problems

Done with Dijkstra:: 09 Graph Theory:: Dijkstra's Algorithm with CSES 08 Shortest Routes I (1671) - YouTube

Do give feedback, please!

:slight_smile:

I will be adding Bellman-Ford and solving more problems starting tomorrow.

Please keep following this series to improve your understanding of graph theory.

Hey, can you help me with this problem?

Check out my DFS

See what i did there? I created a global vector idx and did the following to track the edge being currently explored.

When I come back, I don’t start checking ALL neighbours of vertex ‘u’. I simply continue from where I left. Hope that makes sense?

If we don’t take care of this, we will search ALL edges every time in the following case. I am calling this graph a flower-with-petal graph. Only seven petals in this graph, but imagine what happens if there are 10^5 petals (with O(N^2) complexity)

image

If it doesn’t I am not going to type out more here. I try to make a Eulerian Circuit video on priority and explain this aspect clearly.

Watch out for this video series: - YouTube

round trip cses usaco

Hey guys! Just solved another problem for you guys: High Score and this time we study the “Bellman-Ford” Algorithm.

Hope you’ll love it.

one of the best graph theory tutorial is by Code N Code

Codeforces

Atcoder ABC #346 Solution Discussion

The 2024 ICPC European Championship

New comment(s)

  • BabaYaga_59
  • Submissions

BabaYaga_59's blog

Round Trip CSES problem

This solution is giving wrong answer in 3 test cases which are very large and i am unable to debug those Please Help....;)

Vote: I like it

CSES

CSES Problem Set

Round trip ii.

  • Time limit: 1.00 s
  • Memory limit: 512 MB

Byteland has n cities and m flight connections. Your task is to design a round trip that begins in a city, goes through one or more other cities, and finally returns to the starting city. Every intermediate city on the route has to be distinct.

The first input line has two integers n and m : the number of cities and flights. The cities are numbered 1,2,\dots,n .

Then, there are m lines describing the flights. Each line has two integers a and b : there is a flight connection from city a to city b . All connections are one-way flights from a city to another city.

First print an integer k : the number of cities on the route. Then print k cities in the order they will be visited. You can print any valid solution.

If there are no solutions, print "IMPOSSIBLE".

Constraints

  • 1 \le n \le 10^5
  • 1 \le m \le 2 \cdot 10^5
  • 1 \le a,b \le n

Graph Algorithms

Search code, repositories, users, issues, pull requests...

Provide feedback.

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly.

To see all available qualifiers, see our documentation .

  • Notifications

cses solution

jt112/graph

Folders and files, repository files navigation.

Apelsin Hotel

hotel overview picture

Guest Reviews

Services & amenities.

Suite Room

Standard Room

Comfort Room

Comfort Room

Junior Suite Room

Junior Suite Room

Guest reviews (1).

round trip cses usaco

  • Cleanliness 3.6
  • Amenities 3.6
  • Location 3.6
  • Service 3.6

Book now and leave a review after your stay to earn up to 120 Trip Coins (approx. $1.20 ). Trip Coins can be used to save instantly on room rates.

round trip cses usaco

Property Policies

Property description.

  • Number of Rooms: 81

Frequently Asked Questions

How much does it cost to stay at apelsin hotel, what is the closest airport to apelsin hotel, what are the check-in and check-out times at apelsin hotel, does apelsin hotel provide airport transfer services, what amenities and services does apelsin hotel have, does apelsin hotel have a swimming pool, does apelsin hotel have fitness amenities, does apelsin hotel provide wi-fi, does apelsin hotel have non-smoking rooms, does apelsin hotel provide breakfast, about this property, popular hotels, explore more.

Search Cheap Flights to Elektrostal

Search 400 airlines and 321,000 hotels worldwide.

Stop Planning & Start Exploring

FREE 24 hour cancellation on most flights

Cheap Flights to Elektrostal

Fall in love at first flight with your vacation to Elektrostal by saving a ton of cash on your last-minute cheap flight. There’s no more scouring the internet for a good deal—book your flight to Elektrostal on Hotwire, and you’ll be up, up, and on a getaway in no time.

Because once the wheels are down in Elektrostal, the good times start rolling. So buckle up, you’re in for a fun ride.

Just the right flight

Don’t waste your time on endless searches for cheap airline tickets oneway or roundtrip. We’ll have you on your way to Elektrostal with a tiny bag of pretzels in your hand before you can say “tray tables in the upright position”—and for a ticket price that works for your vacay budget.

So all you have to worry about is where you’re headed after the VKO airport.

Frequently Asked Questions About flights to Elektrostal

What is the cheapest month to fly to elektrostal.

Airline ticket prices fluctuate all the time, depending on the day of the week or the month of the year. The cheapest round trip flights to Elektrostal are in , but when you book your flight on Hotwire, savings are always in season.

How many airlines fly to Elektrostal?

Variety is the spice of life, even when it comes to booking your next trip. Want options for airlines? You’ll find  to choose from for your flight to Elektrostal.

What airport is best to fly into Elektrostal?

When you’re planning your trip to Elektrostal, convenience is the name of the game. Luckily, Elektrostal Zhukovsky Airport is nearby so you can deplane and get going on checking off everything on your Elektrostal must-do list.

How much are flights to Elektrostal?

Got very cheap flights on your vacation itinerary? When you book your airline tickets to Elektrostal on Hotwire, you may just get what’s on your getaway wish list. With tickets as low as , you’ll have leftover cash for at least a magazine and a bottle of water at the airport book store.

How to get cheap flights to Elektrostal?

The trick to saving a stack of cash on your flight to Elektrostal? Snatch up that Hotwire flight deal when you see a killer rate because it could be gone in a flash. And with flights as low as  right now, why wait?

Can I fly to Elektrostal right now?

With recent COVID-19 closures and reopenings, many people are wondering, “Is it safe to travel to  right now?” When it’s time to book your flight, be sure to check out the most up-to-date information on all safety measures, any restrictions, and  guidance on traveling during the coronavirus  pandemic.

Popular Flight Routes

  • Top Flight Routes

Nearby Cities

  • Flights to Moscow
  • Atlanta to New York
  • Detroit to Las Vegas
  • Dallas to Atlanta
  • Dallas to Yosemite National Park
  • Toronto to Edmonton
  • Chicago to Tulum
  • Houston to Lake Tahoe
  • Chicago to Las Vegas
  • Dallas to Miami
  • Dallas to Lake Tahoe
  • New York to Miami
  • New York to Las Vegas
  • Miami to Atlanta
  • Minneapolis St Paul to Fort Walton Beach Destin
  • Dallas to Branson
  • Cleveland to Vero Beach
  • Managua to Miami
  • Atlanta to Boston
  • Austin to Tulum
  • Calgary to Vancouver

Flights to Our Favorite Destinations

  • Flights to St. Petersburg
  • Flights to Mogot
  • Flights to Kaliningrad
  • Flights to Sochi
  • Flights to Vladivostok
  • Flights to Kharp
  • Flights to Irkutsk
  • Flights to Kazan
  • Flights to Novosibirsk
  • Flights to Yekaterinburg
  • Flights to Kyzyl
  • Flights to Krasnodar
  • Flights to Makhachkala
  • Flights to Gay
  • Flights to Gelendzhik

Save more. Do more.

  • Vacation Rentals
  • Restaurants
  • Things to do
  • Elektrostal Tourism
  • Elektrostal Hotels
  • Elektrostal Bed and Breakfast
  • Flights to Elektrostal
  • Elektrostal Restaurants
  • Things to Do in Elektrostal
  • Elektrostal Travel Forum
  • Elektrostal Photos
  • Elektrostal Map
  • All Elektrostal Hotels
  • Hotels near (ZIA) Zhukovsky International Airport
  • Hotels near (VKO) Vnukovo Airport
  • Hotels near (DME) Domodedovo Airport
  • Lombok Senggigi Hotel
  • Dreams Jade Resort & Spa
  • Secrets The Vine Cancun
  • Hotel Riu Palace Cabo San Lucas
  • Secrets Royal Beach Punta Cana
  • The LINQ Hotel + Experience
  • Finest Punta Cana By The Excellence Collection All Inclusive
  • ARIA Resort & Casino
  • Disney's Caribbean Beach Resort
  • Atelier Playa Mujeres
  • Beaches Turks & Caicos
  • Hotel Chester
  • Giraffe Manor
  • Secrets Akumal Riviera Maya
  • Park MGM Las Vegas
  • Popular All-Inclusive Resorts
  • Popular Beach Resorts
  • Popular Family Resorts
  • Popular All-Inclusive Hotels
  • Popular Hotels With Waterparks
  • Popular Honeymoon Resorts
  • Popular Luxury Resorts
  • Popular All-Inclusive Family Resorts
  • Popular Golf Resorts
  • Popular Spa Resorts
  • Popular Cheap Resorts
  • Flights to Khimki
  • Flights to Staroe Bobrenevo
  • Flights to Krasnogorsk
  • Flights to Mytishchi
  • Flights to Balashikha
  • Flights to Domodedovo
  • Flights to Podolsk
  • Flights to Kolomna
  • Flights to Sergiyev Posad
  • Flights to Lyubertsy
  • Cheap flights from New York City to Las Vegas
  • Cheap flights from New York City to Miami
  • Cheap flights from New York City to Tel Aviv
  • Cheap flights from New York City to Kingston
  • Cheap flights from New York City to Los Angeles
  • Cheap flights from New York City to Santo Domingo
  • Cheap flights from New York City to Fort Lauderdale
  • Cheap flights from New York City to Paris
  • Cheap flights from New York City to Montego Bay
  • Cheap flights from New York City to Orlando
  • Flights to San Juan
  • Flights to Miami
  • Flights to Orlando
  • Flights to Tel Aviv
  • Flights to Los Angeles
  • Flights to Rome
  • Flights to Hong Kong
  • Flights to Barcelona
  • Flights to Las Vegas
  • Flights to Manila
  • Basic Economy Flights to Elektrostal
  • Economy Flights to Elektrostal
  • Premium Economy Flights to Elektrostal
  • Business Class Flights to Elektrostal
  • First Class Flights to Elektrostal
  • Flights to Zhukovsky International Airport
  • Flights to Vnukovo Airport
  • Flights to Domodedovo Airport
  • Flights to Sheremetyevo Airport
  • Ural Airlines Reviews
  • Ural Airlines Deals
  • GreenLeaders
  • Elektrostal
  • Things to Do
  • Travel Stories
  • Rental Cars
  • Add a Place
  • Travel Forum
  • Travelers' Choice
  • Help Center

Cheap Flights to Elektrostal - Elektrostal Flights

  • Europe    
  • Russia    
  • Central Russia    
  • Moscow Oblast    
  • Elektrostal    
  • Elektrostal Flights

Find the best flight to Elektrostal

Popular airlines flying to moscow.

round trip cses usaco

Top Attractions in Elektrostal

Electrostal history and art museum, statue of lenin, park of culture and leisure, museum and exhibition center.

USACO Forum

Distinct colors - cses.

I was trying to solve a question on cses - Distinct Colors , My solution based on the book Competitive Programmer’s Handbook by Antti Laaksonen page number 170(Merging data structures)

What I want to know is that when I swap the two maps in the above code using

The code gets Accepted , but when I do not swap these maps I get a TLE , here is a quote from the book :

The merging of nodes can be done as follows: We go through the children of s and at each child u merge d[ s ] and d[ u ]. We always copy the contents from d[ u ] to d[ s ]. However, before this, we swap the contents of d[ s ] and d[ u ] if d[ s ] is smaller than d[ u ]. By doing this, each value is copied only O(log(n)) times during the tree traversal, which ensures that the algorithm is efficient.

how does swapping the maps according to their size ensures that each element would be at most copied O(log(N)) times?

If all the colors are unique, then the complexity to copy one map to another would-be O(N) right? That would make total complexity O(N^2) .

:bowing_man:

Apelsin Hotel

hotel overview picture

Guest Reviews

Services & amenities.

Suite Room

Standard Room

Comfort Room

Comfort Room

Junior Suite Room

Junior Suite Room

Guest reviews (1).

round trip cses usaco

  • Cleanliness 3.6
  • Amenities 3.6
  • Location 3.6
  • Service 3.6

Book now and leave a review after your stay to earn up to 120 Trip Coins (approx. US$1.20 ). Trip Coins can be used to save instantly on room rates.

round trip cses usaco

Property Policies

Property description.

  • Number of Rooms: 81

Frequently Asked Questions

How much does it cost to stay at apelsin hotel, what is the closest airport to apelsin hotel, what are the check-in and check-out times at apelsin hotel, does apelsin hotel provide airport transfer services, what amenities and services does apelsin hotel have, does apelsin hotel have a swimming pool, does apelsin hotel have fitness amenities, does apelsin hotel provide wi-fi, does apelsin hotel have non-smoking rooms, does apelsin hotel provide breakfast, about this property, popular hotels, explore more.

IMAGES

  1. Round Trip II

    round trip cses usaco

  2. How To Look For The Cheapest Round Trip Airfare

    round trip cses usaco

  3. Round Trip CSES Graph Problem

    round trip cses usaco

  4. CSES-Graphs- Message Routes, Building Teams, Round Trip

    round trip cses usaco

  5. Solution

    round trip cses usaco

  6. What Does Round Trip Mean?

    round trip cses usaco

VIDEO

  1. Fort Boonesborough State Park

  2. An Unforgettable Expedition: Springdales Japan Adventure 2023

  3. Turkish Multicouples • Halo

  4. Chicago Bears Trade Rumors Are HOT: NFL Insider Proposes Justin Fields Trade Idea To Atlanta Falcons

  5. 2017 USACO Gold Round 3 #1 Part 1

  6. USACO 2023 Open Silver Problem 2 Field Day

COMMENTS

  1. Topological Sort · USACO Guide

    A topological sort of a directed acyclic graph is a linear ordering of its vertices such that for every directed edge u\to v u → v from vertex u u to vertex v v, u u comes before v v in the ordering. There are two common ways to topologically sort, one involving DFS and the other involving BFS. Resources. CSA. Topological Sorting.

  2. Graph 04: Round Trip :: Cycle Retrieval, Cycle Detection ...

    Byteland has n cities and m roads between them. Your task is to design a round trip that begins in a city, goes through two or more other cities, and finally...

  3. mrsac7/CSES-Solutions: Accepted solutions of CSES problemset

    1741 - Area of Rectangles. 2429 - Grid Completion. 1752 - Creating Offices. 1075 - Permutations II. 2415 - Functional Graph Distribution. 1685 - New Flight Routes. 2418 - Grid Path Construction. Accepted solutions of CSES problemset. Contribute to mrsac7/CSES-Solutions development by creating an account on GitHub.

  4. cses graph session editorial(incomplete)

    Editorial for Flight Route Check. Ques LinK. Run the dfs from any node and then check all nodes are visited or not. if any node is not visited, u will get the answer. Also check is there any node is present in graph whose outdegree is zero. if yes then u can visited from this node to any node. Else the answer is YES.

  5. Solution

    A free collection of curated, high-quality competitive programming resources to take you from USACO Bronze to USACO Platinum and beyond. Written by top USACO Finalists, these tutorials will guide you through your competitive programming journey. ... CSES - Flight Routes Check. Authors: Michael Cao, Nathan Gong. Language: All. Edit This Page ...

  6. [Video Tutorial Series] Graph Theory: From Beginner to Intermediate

    CSES 14: Round Trip II: 15 Graph Theory:: DFS with Stack to Retrieve Cycle in Directed Graph CSES Round Trip II 1678 - YouTube. CSES 15: Course Schedule: 16 Graph Theory:: Topological Sort with CSES: Course Schedule 1679 - YouTube. CSES 16: Longest Flight Route: Graph 17: Longest Flight Route :: Modified Dijkstras(CSES 16: 1680) - YouTube

  7. CSES

    Your task is to design a round trip that begins in a city, goes through two or more other cities, and finally returns to the starting city. Every intermediate city on the route has to be distinct. Input. The first input line has two integers n and m: the number of cities and roads. The cities are numbered 1,2,\dots,n.

  8. Round Trip CSES problem

    Before contest Codeforces Round 936 (Div. 2) 2 days Register now ... xiaowuc1 → USACO 2023-2024 US Open . E869120 → JOI Spring Training 2024 Online Contest . ... Round Trip CSES problem. By BabaYaga_59, history, 3 years ago, ...

  9. GitHub: Let's build from here · GitHub

    {"payload":{"allShortcutsEnabled":false,"fileTree":{"src":{"items":[{"name":"1068 - Weird Algorithm.cpp","path":"src/1068 - Weird Algorithm.cpp","contentType":"file ...

  10. CSES

    Your task is to design a round trip that begins in a city, goes through one or more other cities, and finally returns to the starting city. Every intermediate city on the route has to be distinct. Input. The first input line has two integers n and m: the number of cities and flights. The cities are numbered 1,2,\dots,n.

  11. Solution

    new BufferedReader(new InputStreamReader(System.in)); PrintWriter out = new PrintWriter(System.out); A free collection of curated, high-quality competitive programming resources to take you from USACO Bronze to USACO Platinum and beyond. Written by top USACO Finalists, these tutorials will guide you through your competitive programming journey.

  12. GitHub

    Saved searches Use saved searches to filter your results more quickly

  13. CSES

    https://cses.fi/problemset/task/1164 In this problem, why do we sort by starting time? The classic scheduling problem usually has us schedule by the end time, so I ...

  14. Solution

    A free collection of curated, high-quality competitive programming resources to take you from USACO Bronze to USACO Platinum and beyond. Written by top USACO Finalists, these tutorials will guide you through your competitive programming journey. ... CSES - Flight Routes. Author: Benjamin Qi. Language: All. Edit This Page. Appears In. Gold ...

  15. Apelsin Hotel, 2024

    (Simplify your booking process with our one-stop booking service on Trip.com) Destination. Elektrostal' Check-in. 0 nights. Check-out. Rooms and Guests. 1 room, 2 adults, 0 children. Update. All Properties in Elektrostal' Apelsin Hotel. Noginskoye Shosse 36B, Elektrostal', Moscow region, Russia Show on Map.

  16. Cheap Flights to Elektrostal (VKO),

    Looking for cheap flights to Elektrostal (VKO)? Browse through our last minute VKO flights from . Save up to 40% with our hot rate flight deals. Book with Hotwire today!

  17. Solution

    Written by top USACO Finalists, these tutorials will guide you through your competitive programming journey. A free collection of curated, high-quality competitive programming resources to take you from USACO Bronze to USACO Platinum and beyond. ... CSES - Game Routes. Authors: Andrew Wang, Sofia Yang. Language: All. Edit This Page. Appears In ...

  18. 5 Cheap Flights to Elektrostal, Russia

    Book Cheap Flights to Elektrostal: Search and compare airfares on Tripadvisor to find the best flights for your trip to Elektrostal. Choose the best airline for you by reading reviews and viewing hundreds of ticket rates for flights going to and from your destination.

  19. Distinct Colors

    USACO Forum. General Questions. kushagra December 3, 2020, 8:15am #1. I was trying to solve a question on cses - Distinct Colors, My solution based on the book Competitive Programmer's Handbook by Antti Laaksonen page number 170 (Merging data structures) #include<bits/stdc++.h> using namespace std; const int Mxn = 2e5; unordered_set<int> adj ...

  20. Apelsin Hotel,Elektrostal' 2023

    Find the best hotel at the best rate. Over 1,200,000 hotels in more than 200 regions. 24/7 Customer Service.