The Celebrity Problem
TThe Celebrity Problem in Java is a classic algorithmic puzzle that challenges programmers to efficiently identify a special individual within a group who is known by everyone but knows no...
Maximum Product of Indexes of next greater on Left and Right
Problem Statement You are given an array A. Let us say that the array has indices from 1 to N. For each index i in the array: The quantity L(i)...
Iterative Tower of Hanoi
The Tower of Hanoi puzzle has fascinated mathematicians and puzzle enthusiasts alike for centuries with its elegant simplicity and complex nature. Originally formulated by the French mathematician Édouard Lucas in...
How to efficiently implement K Stacks in a single Array?
Our task is to Implement K stacks that should use only one array. The K stacks must support these functions push(int x, int sn): pushes element x to stack number...
Design a Stack with operations on Middle element
Brief about Stack Data structure: A stack is a linear data structure that follows the principle of Last In First Out (LIFO). This means the last element inserted inside the...
Print Next Greater number of Q queries
Problem statement You are given an integer array of size n and q queries. Your task is to find the next greater element for each query. Each query consists of...
Next Greater Frequency Element
Problem statement Given an array, consisting of n elements, find the next greater frequency element of each element. The next greater frequency element of any element is the first element...
Arithmetic Expression Evaluation
Arithmetic expression evaluation is the process of computing the value of a mathematical expression containing arithmetic operators, such as addition, subtraction, multiplication, and division, along with parentheses and operands. Before...
Next Greater Element
Problem statement Given an array, consisting of n elements, find the next greater element of each element. The next greater element of any element is the first larger element to...
Check for Balanced Parentheses in an Expression
In computer science, balanced parentheses are a common requirement for many programming languages and applications. Balanced parentheses refer to an expression in which all opening and closing parentheses are properly...
How to Solve Stock Span Problem?
What is Stock Span Problem: Stock span problem is a commercial problem where we have a series of N prices on the daily basis. And you need to calculate the...
Implement a Stack Using Single Queue
Problem statement: We have to build a stack with a single queue. What is a Stack? Stack is a linear data structure in which a user can insert and delete...
Implement stack using Priority Queue or Heap
What is a priority queue? The priority queue is a type of queue data structure having one extra feature of giving priority to every element present in the priority queue....
Implement Stack Using Queue
In this article, we explore the implementation of stacks using queues and the interplay between push vs pop operations. Stacks, based on the Last-In-First-Out (LIFO) principle, and queues, based on...
Difference Between Array, Queue and Stack
Array: An Array is a collection of elements which are stored in a contiguous memory. The idea is simple i.e. to store the multiple elements together. Due to which we...
Difference between Stack and Queue Data Structures
Data structures are an essential part of computer science and programming. Two fundamental data structures that are frequently used are stacks and queues. These data structures provide a way to...
Stack and Queues in python
In data structures, stack and queue are part of linear data structure. Stack Stack follows the principle of LIFO (Last in First out) i.e. element which is inserted at last...
Reverse a stack without using extra space in O(n)
Problem Statement In this problem, we are given a stack. We have to reverse the stack without using extra space in O(n). Problem Statement Understanding As we know, reversing a...
Play With Brackets
Concepts Used Stack Difficulty Level Easy. Problem Statement : Rashid is given a set of open and closed brackets of each type such as [ , ], ( , )...
Stack Challenge
Concepts Used Stack Difficulty Level Hard Problem Statement : Rahul and Ritika are playing a game of stacks where each of them are having a stack A and B of...
K overlapping segment
Concepts Used: Stack. Difficulty Level: Medium. Problem Statement : Arnab is hosting a party but he has only k seats. Guest have come at different times and leave at different...
Max Rectangle
Concepts Used: DP/recursion and Stack. Difficulty Level: Hard. Problem Statement : Given a 2D binary matrix filled with 0’s and 1’s, find the largest rectangle containing all ones and print...
Samir String
Concepts Used: Stack. Difficulty Level: Easy. Problem Statement : Make the minimum number without repetition of the digits such that it follows the sequence given in the string. 'I' represents...
Next Greater Element
Concepts Used: Stacks. Difficulty Level: Medium. Problem Statement : Arnab is standing in a queue and he is irritated by the tall man standing after him, as he is obstructing...
Sort stack
Concepts Used: Stacks Difficulty Level: Easy. Problem Statement : Given a stack of integers, sort it in ascending order using another temporary stack. See original problem statement here Solving Approach:...
Remove all adjacent duplicates
Concepts Used Stack Difficulty Level Easy Problem Statement : Given a string str of lowercase letters, a duplicate removal consists of choosing two adjacent and equal letters, and removing them....
Get Minimum Element from Stack
Get minimum element from stack is a common problem in computer science. A stack is a data structure that follows the Last-In-First-Out (LIFO) principle, where elements are added and removed...
Beach House
Concepts Used: Stack. Difficulty Level: Hard. Problem Statement : Nishant wants to buy a plot of land, which faces the beach. He will buy only a rectangular plot. So he...
Compile Code
Concepts Used: Stacks. Difficulty Level: Medium. Problem Statement : Given a string of open angular bracket ‘<‘ and closed bracket ‘>’. The task is to find the length of longest...
Arrogant Students
Concepts Used: Stacks Difficulty Level: Hard. Problem Statement : Sachin is teaching a group of N students. Now every student has an arrogance level. He make all the N students...