Iteratively print the leaf to root path for every leaf node in a binary tree
Given a binary tree, write an iterative algorithm to print the leaf-to-root path for every leaf node. Use of recursion is prohibited.
Category: Stack
Invert Binary Tree – Iterative and Recursive Solution
Given a binary tree, write an efficient algorithm to invert it.
Longest Increasing Subsequence Problem
The Longest Increasing Subsequence (LIS) problem is to find a subsequence of a given sequence in which the subsequence’s elements are in sorted order, lowest to highest, and in which the subsequence is as long as possible. This subsequence is not necessarily contiguous or unique.
Merging Overlapping Intervals
Given a set of intervals, print all non-overlapping intervals after merging the overlapping intervals.
Decode a given sequence to construct a minimum number without repeated digits
Given a sequence consisting of I and D, where I denotes the increasing sequence and D denotes the decreasing sequence, decode the sequence to construct a minimum number without repeated digits.
Find ancestors of a given node in a binary tree
Given a binary tree, find all ancestors of a given node in it.
Inorder Tree Traversal – Iterative and Recursive
Given a binary tree, write an iterative and recursive solution to traverse the tree using inorder traversal in C++, Java, and Python.
Preorder Tree Traversal – Iterative and Recursive
Given a binary tree, write an iterative and recursive solution to traverse the tree using preorder traversal in C++, Java, and Python.
Postorder Tree Traversal – Iterative and Recursive
Given a binary tree, write an iterative and recursive solution to traverse the tree using postorder traversal in C++, Java, and Python.
Reverse level order traversal of a binary tree
Given a binary tree, print its nodes level by level in reverse order, i.e., print all nodes present at the last level first, followed by nodes of the second last level, and so on… Print nodes at any level from left to right.
Check if two binary trees are identical or not – Iterative and Recursive
Write an efficient algorithm to check if two binary trees are identical or not, i.e., if they have identical structure and their contents are also identical.
Reverse text without reversing individual words
Given a line of text, reverse the text without reversing the individual words.