Itsy's Magic CardsItsy needs your help with her magic cards. Her magic cards grant her special spiderwitch powers. Un...

Color The GraphYou are given an acyclic, bidirectional graph with NNN nodes and M edges. The nodes are numbered fro...

Flow on TreeMr. Kaboom has recently learned about maximum flow. Now his friend Mr. Taboom gave him this problem....

Kingdom  Great Roads of DestinyShin wants to be the “Great General of the Heaven”. It is his dream. But becoming a “Great General o...

Bad XOR 2 (Hard)So after successfully becoming many people's nightmare, XOR has struck again, this time to haunt you...

Act of Random Kindness (Hard)Sammy and Meera liked adventures a lot. Once in a while they used to set out adventures. This time t...

Sofdor Ali's Black and White TreeSofdor Ali loves Computer Science. He prefers hexadecimal number system to decimals, just because it...

Kingdom of CodeKingdom CODE is the most peaceful place in the universe. King NOVOSH and Queen ALMIDA is ruling this...

Spanning TreeThere are N nodes in a tree. You can start from any node of that tree and you have to come back to t...

Flyover in TwinlandRio has become the president of Twinland. Now he wants to develop his country to fulfill his promise...

Ghosh vs DattaAbout two hundred years ago, a serious dispute evoked between the two neighboring colonies of Khulna...

Prime AvoiderMr. X is a friend of Hafiz bhai. Mr. X loves to play with numbers in his leisure but he hates prime ...

Darth Vader and 3PO on a Tree!Did you watch Star Wars yet? No? You should in your free time. Now back to Darth Vader and 3PO. Dart... 
Keep MovingBalurmath is a city which has N interesting tourist spots, which are connected between themselves by...

Village Fair 2There are N houses in a village far away from here. They are numbered from 1 to N. For this problem ...

Circuit BreakerIn your free time, you like to design various electrical circuits to give a hard time to your local ...

Traveling Policy of AjobdeshIn Ajobdesh, there are multiple cities and one of them is considered as the capital city. Obviously,...

War in the Wizarding WorldThere is a deadly war going on between two countries (Bitland and Byteland) in the wizarding world. ...

A Boring GameAlice and Bob are playing a game with a tree with n nodes. Alice always plays first, and the two pla...

Gold MinesThe city of gridland is a grid with n rows and m columns. The city can be divided into n*m cells. A ...

Road Minister TechboyTechboy is appointed as the minister of roads and highway in his country BetterNotNameIt. Now he ...

Christmas TreeProfessor Rio has an amazing Christmas tree. Unlike other trees, this Christmas tree has some specia...

Reverse The MagicYou are probably familiar with the technique of representing a Tree as an array of integers using Eu...

Big Bang TheoryDr. Sheldon Cooper is working on a project that works on the 2D concept of the universe. In this pro...

The Spy CatsAfter Max and Alexis's initial plan to conquer the world with kitten armies failed, they started a n...

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