Find all duplicate elements in a limited range array
Find the duplicate numbers in an integer array of size n that contains elements between 1 and n, at least one of which repeats.
Tag: Easy
Remove all nodes from a linked list that matches a given key
Given a linked list, remove all nodes from it that match a given key.
Find perimeter of an Island
Given a binary matrix in which the values 0 and 1 correspond to land and water, respectively, and the connected ones form exactly one island, find the perimeter of an island.
Find length of the longest palindrome possible from a string
Given a string, find the length of the longest palindrome possible from its characters.
Generate an array with the set bit count of each index
Given a positive number n, construct an integer array of length n where each index stores the count of 1’s in the binary representation of the index.
Check if a string can be constructed from another string
Given two strings, check if the second string can be constructed from characters of the first string, where each character of the first string can be used only once in the second string.
Determine if a string is a subsequence of another string
Given two strings, check if the second string is a subsequence of the first string.
Check children-sum property in a binary tree
Given the root of a binary tree, determine if the binary tree holds children-sum property. For a tree to satisfy the children-sum property, each node’s value should be equal to the sum of values at its left and right node.
Count nodes in a BST that lies within a given range
Given a BST, count the total number of nodes that lie within a given range.
Construct a complete binary tree from its linked list representation
Given a linked list, construct a complete binary tree from it. Assume that the order of elements present in the linked list is the same as that in the complete tree’s array representation.
Check if removing an edge can split a binary tree into two equal size trees
Given a binary tree, check if removing an edge can split it into two binary trees of equal size.
Determine whether a BST is skewed from its preorder traversal
Given an array representing the preorder traversal of a BST, determine whether it represents a skewed BST or not. In a skewed BST, each node’s descendants are either smaller or larger than the node itself.