Iterative Postorder Traversal of N-ary Tree
Given an N-ary tree, the task is to find the post-order traversal of the given tree iteratively. Examples: Input: 1 / | \ 3 2… Read More »
Category Archives: Stack
Reduce the string to minimum length with the given operation
Given a string str consisting of lowercase and uppercase characters, the task is to find the minimum possible length the string can be reduced to… Read More »
Sort the given stack elements based on their modulo with K
Given a stack of integers and an integer K, the task is to sort the elements of the given stack using another stack in the… Read More »
Check if the bracket sequence can be balanced with at most one change in the position of a bracket | Set 2
Given a bracket sequence as a string str, the task is to find whether the given string can be balanced by moving at most one… Read More »
Check if any K ranges overlap at any point
Given N ranges [L, R] and an integer K, the task is to check if there are any K ranges which overlap at any point.… Read More »
Stack in Python
A stack is a linear data structure that stores items in a Last-In/First-Out (LIFO) or First-In/Last-Out (FILO) manner. In stack, a new element is added… Read More »
Find the winner of the Game to Win by erasing any two consecutive similar alphabets
Given a string consisting of lower case alphabets. Rules of the Game: A player can choose a pair of similar consecutive characters and erase them.… Read More »
Convert ternary expression to Binary Tree using Stack
Given a string str that contains a ternary expression which may be nested. The task is to convert the given ternary expression to a binary… Read More »
Find all unique pairs of maximum and second maximum elements over all sub-arrays in O(NlogN)
Let represent the ordered pair of the second maximum and the maximum element of an array respectively. We need to find all such unique pairs… Read More »
Python | Stack using Doubly Linked List
A stack is a collection of objects that are inserted and removed using Last in First out Principle(LIFO). User can insert elements into the stack,… Read More »
InfyTQ 2019 : Find the position from where the parenthesis is not balanced
Given a string str consisting of parenthesis from [ “(” , “)” , “{” , “}” , “[” , “]” ]. If the String is… Read More »
Introduction to Data Structures | 10 most commonly used Data Structures
A data structure is a particular way of organizing data in a computer so that it can be used effectively. The idea is to reduce… Read More »
Implementing Forward Iterator in BST
Given a Binary search tree, the task is to implement forward iterator on it with the following functions. curr(): returns the pointer to current element.… Read More »
Nodes from given two BSTs with sum equal to X
Given two Binary search trees and an integer X, the task is to find a pair of nodes, one belonging to the first BST and… Read More »
Triplet with a given sum in BST | Set 2
Given a binary search tree, and an integer X, the task is to find if there exists a triplet with sum X. Print Yes or… Read More »
