# Data Structure Problems

#### Count the Chaos

Imagine, you have an array of integers of size N. At each index of this array is a unique integer fr...

#### Easy Prime!

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

#### Matching Brackets

You will be given a sequence of opening and closing brackets of different types ((, ), [, ], {, and ...

#### Set Union

Given two sets of integers, print the set containing the union of the two input sets. For example, ...

#### Device ID

A device ID is a distinct number associated with a smartphone or similar handheld device. Every smar...

#### Rivalry Friends

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

#### Not As Hard As It Seems

Sakib and Shamim are good friends. As Sakib is a little naughty, every night before exam he disturbs...

#### Modulo

Let’s get straight into the problem. In ths problem, here will be multiple test cases. In each test ...

#### Another Query on String

You are given a string S (of length n) consisting of alphabets only. You need to perform m queries o...

Can you imagine? Mad Engineer Aksir finally got the job. His job is to set up toggle switch for a s...

#### Dynamic Tree

You are given a tree containing N vertices. The vertices are numbered from 1 to N. A tree with N ver...

#### Crayons

Five friends A, B, C, D and E has come to a shop to buy crayons for their art project. They need cra...

#### Hamming Distance

Hamming distance between two binary strings of equal length is the number of mismatches between ever...

#### Find the Good Sequence

Let’s say two numbers are called “good” if their difference is at least 2. Similarly, a sequence is...

#### Byang and War Tactics

Byang is learning about War Tactics from Raat, a famous martial arts master, who has successfully tr...

#### Sofdor Ali and Bracket Sequence

Sofdor Ali has invented a new game. He asked his assistant Jong Bahadur ( who happens to be a monkey...

#### Data Structure

The operations that are performed in a data structure can be categorized into two types: query and u...

#### Distinct Dishting

You are given an array of N integers. Then there will be Q commands of the following type: 1) Chang...

#### Smallest Subarray

You are given an array A of N integers A1, A2, A3, …, AN . If we select two indices (1 ≤ i ≤ j ≤ N) ...

#### Array Simulation

You are given an array of N elements. Initially all the indices have a value of 0. You have to do fo...

#### Primary Key

“Clarity-Lon” is the new awesome e-commerce based startup that went to the top of the chart within...

#### Rio and Inversion

One day Rio was returning home from his university and unfortunately lost his phone on the way. He a...

#### Special Pair

Mr. X is an “array pagla” person. He loves doing different types of things with arrays. Today Mr. X ...

#### Village Fair 2

There are N houses in a village far away from here. They are numbered from 1 to N. For this problem ...

#### Maintain the Queue

“Ajob Desh” is a strange country. Anyone who wants to buy train tickets need to go to the railway st...

#### Subset of Sequences

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

#### Perseus and The New Challenge

The life of princess Andromeda, the daughter of King Cepheus and Queen Cassiopeia of Ados, is in dan...

#### Mario and Princess Peach

The world of Mario can be imagined as 2D grid of N rows and M columns–containing a total of N × M ce...

#### Final Days of Goldfinger

We see agent Bond once again being called in time of a great need. The vile criminal Auric Goldfinge...

#### Smart Query Handler

Bit operators perform bit-wise operations between two binary numbers. Wikipedia says, binary operat...

#### Earthquake!

Most houses are not as safe as they could be. Earthquake engineering is an interdisciplinary branch ...

#### Expandable ListView

Minas is working on his new language. He want to add a feature call expandable listview. Here he exp...