Lexicographical Smallest StringThere is a string sss of length nnn containing lowercase letters and an integer kkk. Among the lette...

Hardest Problem EverProf.Dr.DP is very famous professor. He is expert (actually legendary grandmaster) in Dynamic Progra...

String Is Not That EasyLet's consider a string S which is obtained by concatenating the nonnegative integers from 0 to 102...

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

PasswordsAlice wants to extract some passwords from a random string. A password can have any number of charac...

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

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... 
Diagonal SumGiven an N*N size matrix, you have to rearrange the elements of the matrix in such a way that the d...

Dominoes ForeverOnce when I was little, my father took me to a tobacco shop! It is surprising, but true. He asked th...

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

Game of StringsRedoan is very fond of strings. He wants to go on a spree of solving string problems. His own teamma...

Problem Setter CrisisCompetitive Programming is very popular in Leading University. There are many great achievements of ...

Estimation of TechboyTechboy works in a software company. He codes in Node.js and React. Every now and then he has to giv...

Find NSUPSGiven a string s, find the number of subsequence in s which forms the word "NSUPS". A subs...

BuildingsThere are n buildings in a row. The height of the i'th building is hi. You have ৳k. It is the amount...

Assigning WorkstationsPenelope is part of the admin team of the newly built supercomputer. Her job is to assign workstati...

Déjà VuThor, the Thunder God is fighting a horde of monsters in a cave. The cave is so narrow that it can b...

EkupaiHacker robot Ekupai is trying to hack a supercomputer. He needs a cheat code X to hack this computer...

Fantastic FoodAs we all know that Alice and Bob just landed in Fantastic World and are going to stay for the next ...

Train HijackYou and your friend Daneliya Tuleshova are planning to hijack a train. Your friend will go inside a...

Permutations and DivisorsLet P be a permutation of length n where each value from 1 to n occurs exactly once. A subsequence o...

Subset ANDYou are given an array A of n integers and an integer k. You need to find if there is any nonempty ...

Birthday GiftsToday is Luke's birthday. Mr. Phil Dunphy (Luke's father) has thrown a birthday party for him and de...

RememberRemainderZarin is a sadist. She loves to give problems to her close people. Today she gives you an array cons...

Find the Good SequenceLet's say two numbers are called "good" if their difference is at least 2. Similarly, a se...

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