Combinatorics Problems

You are given an acyclic, bidirectional graph with N nodes and M edges. The nodes are numbered from ...

• By RamprosadG
• Combinatorics, Graph, Tree
• Moderate
• 22/28 Solutions
• 86 Submissions

Milo has a string S of length L. Tutu picks a random prefix and Mota picks a random suffix of S. Now...

• Combinatorics, Counting
• Moderate
• 9/18 Solutions
• 28 Submissions

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

• By ridowan007
• Combinatorics, Counting, DP
• Moderate
• 90/116 Solutions
• 194 Submissions

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

• By TarifEzaz
• Constructive, Counting
• Moderate
• 26/63 Solutions
• 152 Submissions

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

• By Bhadra
• Combinatorics, Counting
• Moderate
• 8/10 Solutions
• 29 Submissions

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

• By jackal_1586
• Counting, MatrixExponentiation
• Moderate
• 5/16 Solutions
• 45 Submissions

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 ...

• By Alim14
• Combinatorics, Counting
• Moderate
• 68/80 Solutions
• 212 Submissions

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

• By Ariful_Efath
• Counting, NumberTheory
• Moderate
• 25/31 Solutions
• 101 Submissions

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

• By Alim14
• Combinatorics, Counting
• Moderate
• 5/14 Solutions
• 23 Submissions

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

• By TarifEzaz
• Combinatorics, Counting
• Moderate
• 9/16 Solutions
• 35 Submissions

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

• By forthright48
• Combinatorics, Counting, NumberTheory
• Moderate
• 8/41 Solutions
• 194 Submissions

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

• By Kryptonyte
• Combinatorics, Counting
• Moderate
• 9/14 Solutions
• 54 Submissions

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

• By TarifEzaz
• Combinatorics, Counting
• Moderate
• 17/30 Solutions
• 77 Submissions

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

• By ridowan007
• Combinatorics, Counting, DataStructure
• Moderate
• 40/60 Solutions
• 302 Submissions

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

• By mehdi_
• Combinatorics, Counting, NumberTheory
• Moderate
• 11/16 Solutions
• 97 Submissions

"There was a break-in of Gringotts Wizarding Bank on 1 May, 1998, during the height of the Secon...

• By Sherlock221b
• Bitmask, Combinatorics, Counting, DP
• Moderate
• 8/20 Solutions
• 36 Submissions

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

• Combinatorics
• Moderate
• 29/104 Solutions
• 435 Submissions

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

• By Sherlock221b
• Counting, NumberTheory
• Moderate
• 20/40 Solutions
• 189 Submissions

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

• By hasan169
• Combinatorics
• Moderate
• 35/139 Solutions
• 657 Submissions

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

• By TarifEzaz
• Combinatorics, Counting
• Moderate
• 162/200 Solutions
• 578 Submissions