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.
Tag: Easy
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.
Find number of customers who could not get any computer
Given an integer representing the capacity of a cyber cafe and a sequence representing entry/exit logs of customers, find the total number of customers who could not get any computer.
Find itinerary from the given list of departure and arrival airports
Given a list of departure and arrival airports, find the itinerary in order. It may be assumed that departure is scheduled from every airport except the final destination, and each airport is visited only once.
Evaluate a Binary Expression Tree
Evaluate a given binary expression tree representing algebraic expressions. A binary expression tree is a binary tree, where the operators are stored in the tree’s internal nodes, and the leaves contain constants.
Check if each node of a binary tree has exactly one child
Given a binary tree, check if each node has exactly one child or not. In other words, check whether the binary tree is skewed or not.
Count triplets which form an inversion in an array
Given an array, count the total number of triplets, which leads to an inversion. If (i < j < k) and (A[i] > A[j] > A[k]), then we can say that triplet (i, j, k) formed an inversion in an array A.
Connect `n` ropes with minimal cost
Given n ropes of different lengths, connect them into a single rope with minimum cost. Assume that the cost to connect two ropes is the same as the sum of their lengths.
Construction of an expression tree
Construct an expression tree from a given postfix notation and print the infix notation. The binary expression tree is a binary tree whose leaves are operands, such as constants or variable names, and the other nodes contain operators.
Print complete Binary Search Tree (BST) in increasing order
Given a level order representation of a complete binary search tree, print its elements in increasing order.