# Combinatorics Problems

#### Geometry Forever

Fear no more, this is a problem of geometry! When Moyna was little, he had a math teacher named Shu...

#### Meeting Place

There is an N*N grid where (r,c) denotes a cell number where r means row number, c means column numb...

#### Circle of Death

Abir is a school going boy, who loves math. Also, he loves to play with stones. Recently he invented...

#### Irregular Is Tough, Regular Is Easy!

Dr. Bari is working on some chemical formation. He believes that chemicals and shapes that are regul...

#### Compute the Combination

Let P = C(N,0) - C(N,1) + C(N,2) - C(N,3) + … + C(N,N); where C(n,r) is “n choose r”. You are given...

#### Trivial Summation

The problem statement is so small. Give you four integers r, a, b, d. Find the summation of all numb...

#### How Many Paths?

You are at the top left corner[position (1,1)] of a **R X C ** grid. Your destination is bottom righ...

#### Cook a Dish

Have you ever cooked something? No? Not a problem! Whenever you try to cook something, you need som...

#### Third Dimension

Mr. J wants to learn about combinatorics. He started reading a book on combinatorics and came across...

#### Counting Murgis

Ever since that wicked thief took away some of her murgis (hens, that is), Meena was ever anxious th...

#### I Hate Combinatorics!

Rick and Morty are being hunted by the galactic government. They ran away to the cell dimension. The...

#### Counting is Difficult 2

East West University Computer Programming Club (EWUCoPC) is arranging an Intra-University Programmin...

#### Meera and Solo Chocolates

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

#### XOR Master

Imam has been participating in online programming contests for years. His goal is to become a “Maste...

#### String Play

Milo has a string S of length L. Tutu picks a random prefix and Mota picks a random suffix of S. No...

#### Sofdor Ali's Restaurant

One of Sofdor Ali’s greatest accomplishment was his Biriyani restaurant! Unlike the traditional rest...

Sofdor Ali is the craziest and clumsiest scientist in Bangladesh. He tries to maintain the safety me...

#### Magician's Offer!

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

#### Obligatory IDPC Problem

There are n people busy with arranging the upcoming Inter Department Programming Contest (IDPC) 2016...

#### Mr. Ant and His Problem

Mr. Ant has 3 boxes and the infinite number of marbles. Now he wants to know the number of ways he c...

In the strange neighborhood of Nocu, a lot of people lives pretty happily, or so they think. Like mo...

As some of you already know, Nocu City has a history of having bad neighbors. These bad ones, take a...

#### Subset of Sequences

You will be given a set of sequences. Each sequence is a list of numbers. Two sequences are K-simil...

#### Secret Meeting

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

#### Harry Potter and the Vault of Gringotts

“There was a break-in of Gringotts Wizarding Bank on 1 May, 1998, during the height of the Second Wi...

#### 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...

#### K-th DuoPalindrome

Alice likes playing with Palindromes (strings that read the same backward as forward, such as ‘madam...

#### Easy Peasy Subset Sum

Little Oishee loves to watch TV. But her mother, who is a math teacher, doesn’t like this at all. Sh...

#### Little T2 and Dead Cats

The planet earth has become peaceful again because all the cats are dead. An evil robot named Xorged...

#### This is Too Hard ☹

Many many years ago there was a small country . And all the people there were very weird. They liked...

#### Mag the Mighty Kaidul

The winter is about to come. Mag the Mighty Kaidul is waiting for it for days. It is his favorite se...

#### Mina and Raju

Everyone know about Mina &amp; Raju. They are siblings as well as good friend. The friend-circle of ...