Rivalry FriendsRyo and his girlfriend love to think about challenges. One day h... 
N'th PrimeIn this problem, you will have to print the nth prime number. Th... 
Fast CoPrimeTwo numbers A and B are called coprime if the only common posit...

Magic NumberJack loves to play with numbers. One day, while he was playing w...

Is It a Perfect Square?Given some numbers, can you tell, if the product of these number... 
Challenging LoverGreetings to all of you. You must have heard about our star prog...

Exponential GrowthYou will be given two integers X and N, you have to calculate XN... 
Left PrimePrime numbers are the ones which can only be divided by 1 and th...

A Lack of Common DivisorsGiven a positive integer N, determine how many of the integers b... 
Is Bita Happy?Bita has learned bitwiseoperations recently. She is doing some ...

Easy Prime!There are N numbers in an array. You will have Q queries. In eac...

ModuloLet’s get straight into the problem. In ths problem, here will b...

Solve This Giveaway Problem FirstThis problem is straightforward and easy. You will be given two...

Prime RangePrime Numbers are such numbers which are only divided by 1 and t...

Birthday Gift for SJToday is your best friend SJ’s birthday. You want to buy a birth... 
Phi Numbers in Range!In number theory, Euler’s phi function, denoted as ϕ(n), is an a...

Sofdor Ali and the Puzzle of WeightsSofdor Ali is one of the most famous scientists of Bangladesh. H...

Magician's Offer!Rosi Vidmun is a greedy landlord who likes to grab as much land ...

Equation Equals HazardsYou are given the equation, GCD(A,M) = 1. You have to determine ...

Meera and Solo ChocolatesMeera bought candies from the store. She is now going to distrib...

CoPrime Enemy PairTwo integers A and B are known as coprime or relatively prime i...

Secret MeetingThe world is terrified by Pandas! After a miraculous chemical ex...

Oh FunctionsLet’s define functions f and g as: f(x) = 2 * ( f(x1) + g(x1)...

Largest PrimeA positive integer number n is called a prime number, if it is o...

Correct the SieveSieve of Eratosthenes is a fast algorithm for finding prime numb...

The Game Is Back OnMoriarty is bored again. When he gets bored, the only thing he w...

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

Is It A Square?Shikamaru is the most brilliant student of his class. He is ve...

Chowdhury Saheb & the NumbersYou like short description of problems? Me too! Let’s go to an e... 
Love Letters!Lately Fahim is getting a lot of love letters. A LOT of love let... 
Zacob The BatsmanIt’s known that Zacob is a reliable batsman of LU CSE Cricket Te... 
Laali Vs BessieOne day Raju discovered USACO and from that day he would spend a...

Bignum Arithmetic

Combinatorics

Fast Fourier Transform

Probability & Statistics

Sieve of EratosthenesA beginner's number theory tutorial on Sieve of Eratosthenes.

Euler's Totient FunctionIf you are given a number N, you have to determine how many integers between 1 and N have a GCD of 1 with N.
