# Number Theory Problems

#### N'th Prime

In this problem, you will have to print the nth prime number. The first few prime numbers are given ...

#### Crypto-Number

Walt and Gus have a great rivalry. Recently Gus has developed a cryptographic system. Walt is trying...

#### Correct the Sieve

Sieve of Eratosthenes is a fast algorithm for finding prime numbers in larger ranges. According to W...

#### Easy Prime!

There are N numbers in an array. You will have Q queries. In each query, you can make 2 operations. ...

#### Magic Number

Jack loves to play with numbers. One day, while he was playing with numbers he found something inter...

#### Rivalry Friends

Ryo and his girlfriend love to think about challenges. One day his girlfriend gave him a challenge t...

#### Zacob The Batsman

It’s known that Zacob is a reliable batsman of LU CSE Cricket Team. Also as long as he is on the cre...

#### Ishtiaque and the Rabbit

Mr Ishtiaque is in trouble. A few months ago, he bought 2 rabbits. He wanted to have two pet rabbits...

#### Love Letters!

Lately Fahim is getting a lot of love letters. A LOT of love letters. Since he is confused about whi...

#### Is It a Perfect Square?

Given some numbers, can you tell, if the product of these numbers are a perfect square or not? A nu...

#### Lucky Shirt

Marjokes is a very famous comedy personality in Byteland. He is a poet, a writer, a singer and an ac...

#### Fast Co-Prime

Two numbers A and B are called co-prime if the only common positive factor of the two numbers is 1. ...

#### Left Prime

Prime numbers are the ones which can only be divided by 1 and the number itself. 2, 3, 5, 7, 11, 13 ...

To become economically stable, Saturn has come up with a new kind of business, tree business. At fi...

#### Challenging Lover

Greetings to all of you. You must have heard about our star programmer Rafat bhai. One day he went o...

#### A Lack of Common Divisors

Given a positive integer N, determine how many of the integers between 1 and N are co-prime with N. ...

#### I Am Good

I am trying to become a good guy, because it doesn’t take money to become good. So here’s a short an...

#### Equation Equals Hazards

You are given the equation, GCD(A,M) = 1. You have to determine whether there exists at least one in...

#### Life of Phi

The Great Khami is learning Number Theory. He is very excited to know that Euler’s Totient Function ...

#### Exponential Growth

You will be given two integers X and N, you have to calculate XN modulo 1000000007.

#### Kitchen Decorate

Shira has now decided to decorate her kitchen of height H and width W more precisely, she wants to ...

Today is your best friend SJ’s birthday. You want to buy a birthday present for her. You want to buy...

#### Meera and Solo Chocolates

Meera bought candies from the store. She is now going to distribute those among her N friends. She m...

#### Laali Vs Bessie

One day Raju discovered USACO and from that day he would spend all his time solving problems. Laali ...

#### Relatively Prime

Given a positive integer N, determine how many of the integers between 1 and N are co-prime with N. ...

#### Sofdor Ali and the Puzzle of Weights

Sofdor Ali is one of the most famous scientists of Bangladesh. He is also well known for his puzzle ...

#### Magician's Offer!

Rosi Vidmun is a greedy landlord who likes to grab as much land as he can. Currently he has P square...

#### Co-Prime Enemy Pair

Two integers A and B are known as co-prime or relatively prime if their greatest common divisor GCD ...

#### Secret Meeting

The world is terrified by Pandas! After a miraculous chemical explosion, they became smarter; and ev...

#### Oh Functions

Let’s define functions f and g as: f(x) = 2 * ( f(x-1) + g(x-1) - 1 ) * ( f(x-1) + g(x-1) - 3 ) + 1...

#### Largest Prime

A positive integer number n is called a prime number, if it is only divisible by 1 and n itself, whe...

#### The Game Is Back On

Moriarty is bored again. When he gets bored, the only thing he wants to do is play with Sherlock. So...