Similar Topics

Web Technologies32.1K+ articles

Misc7.7K+ articles

Mathematical5.1K+ articles

Arrays4.2K+ articles

Strings2.1K+ articles

Greedy1.4K+ articles

Sorting1.1K+ articles

Dynamic Programming1.1K+ articles

Searching1.0K+ articles

Tree911+ articles

DSA / Data Structures / Stack

Stack

261+ posts

Why and when to use Stack or Queue instead of Arrays/Lists?

Last Updated: 23 July 2025

Stack:A stack is a linear data structure in which elements are accessed, inserted and deleted from one end called the top of the stack. Stack follows the LIFO ( Last In Fi...read more

article_image

Why do we need Prefix and Postfix notations?

Last Updated: 01 July 2022

Prefix Notation:Prefix notation is the notation in which operators are placed before the corresponding operands in the expression.Example:Infix notation: A + B Prefix not...read more

regular-expression

Implementation of stack using Doubly Linked List

Last Updated: 23 July 2025

Stack and doubly linked lists are two important data structures with their own benefits. Stack is a data structure that follows the LIFO (Last In First Out) order and can ...read more

article_image

doubly linked list

Find common elements of Stack and Queue

Last Updated: 23 July 2025

Given a stack of M elements and a queue of N elements in sorted order. The task is to find out the common elements of the stack and the queue.Examples:Input: stack = [1, 3...read more

two-pointer-algorithm

Minimize deletions such that no even index Array element is same as next element

Last Updated: 23 July 2025

Given an array arr[], the task is to find the minimum number of deletion operations required such that:The newly created array should have an even length.arr[i] ≠ arr[i+1]...read more

Maximum size rectangle binary sub-matrix with all 1s | Set 2

Last Updated: 23 July 2025

Given a binary matrix mat[][] of size n * m, your task is find the maximum area of the rectangle binary-sub-matrix with all 1’s.Examples:Input: mat[][] = [ [0, 1, 1, 0], ...read more

Interchange elements of Stack and Queue without changing order

Last Updated: 23 July 2025

Given a stack St of M elements and a queue Q of N elements. The task is to put every element of stack into the queue and every element of the queue into the stack without ...read more

Geeks Premier League

Geeks-Premier-League-2022

Replacing adjacent opposite sign pairs with their absolute max in an array

Last Updated: 22 April 2025

Given an array arr[] of size n, the task is to find the final array by repeatedly performing the following operations if two elements of opposite signs are adjacent:Remove...read more

article_image

Geeks Premier League

Geeks-Premier-League-2022

Check if two Binary trees are identical after exactly K changes

Last Updated: 23 July 2025

Given two binary trees T1 and T2 and integer K, the task is to check whether both trees are identical or not after making exactly K changes in the first tree. In each chan...read more

Geeks Premier League

Geeks-Premier-League-2022

Inorder Traversal

Count Subarrays with First Element as Minimum

Last Updated: 15 September 2025

Given an array arr[], Find the number of subarrays whose first element is not greater than other elements of the subarray.Examples:Input: arr[] = [1, 2, 1]Output: 5Explana...read more

Geeks Premier League

Geeks-Premier-League-2022

Maximum People Visible in a Line

Last Updated: 15 September 2025

Given an array arr[], where arr[i] represents the height of the i-th person standing in a line, a person i can see another person j if arr[j] is smaller than arr[i] and th...read more

Reverse first K elements of the given Stack

Last Updated: 23 July 2025

Given a stack S and an integer K, the task is to reverse the first K elements of the given stackExamples:Input: S = [ 1, 2, 3, 4, 5, 8, 3, 0, 9 ], K = 4Output: [ 4, 3, 2, ...read more

Find lexicographical smallest string by performing the given operations N times

Last Updated: 23 July 2025

Given a string S of N characters, the task is to find the smallest lexicographical string after performing each of the following operations N times in any order:Remove the...read more

lexicographic-ordering

Maximum count of integers to be chosen from given two stacks having sum at most K

Last Updated: 23 July 2025

Given two stacks stack1[] and stack2[] of size N and M respectively and an integer K, The task is to count the maximum number of integers from two stacks having sum less t...read more

C++ Program For Arranging Single Linked List In Alternate Odd and Even Nodes Order

Last Updated: 23 July 2025

Given a singly linked list, rearrange the list so that even and odd nodes are alternate in the list.There are two possible forms of this rearrangement. If the first data i...read more

...