SDE - Intern

You have been given a Binary Search Tree (BST). Your task is to flatten the given BST to a sorted list. More formally, you have to make a right-skewed BST from the given BST, i.e., the left child of all the nodes must be NULL, and the value at the right child must be greater than the current node.

A binary search tree (BST), also called an ordered or sorted binary tree, is a rooted binary tree whose internal nodes each store a value greater than all the values in the node's left subtree and less than those in its right subtree.

Follow Up :

Can you solve this in O(N) time and O(H)  space complexity?

You are given a positive integer ‘N’ denoting the number of tasks you need to finish. You can directly start performing any task, but some tasks have some prerequisites, i.e. to perform some task you may first need to complete some other tasks.

You are given a list of pairs of dependencies in the form of ( U, V ) which means to perform task ‘U’ you first need to finish the task ‘V’. You need to report whether it is possible to complete all the tasks or not. Return true if it is possible to finish all the tasks else return false.

You are given a Singly Linked List of integers which is sorted based on absolute value.

You have to sort the Linked List based on actual values.

The absolute value of a real number x, denoted |x|, is the non-negative value of x without regard to its sign.

Example:

If the given list is {1 -> -2 -> 3} (which is sorted on absolute value), the returned list should be {-2 -> 1 -> 3}.

You have been given a Binary Search Tree of integers. You are supposed to convert it to a greater sum tree such that the value of every node in the given BST is replaced with the sum of the values of all the nodes which are greater than the value of the current node in the tree.

A Binary Search Tree is a tree, whose internal nodes each store a value greater than all the values in the node's left subtree and less than those in its right subtree.

Note :

You need to modify the given tree only. You are not allowed to create a new tree.

For example:

For the given binary search tree

11 will be replaced by {15 + 29 + 35 + 40}, i.e. 119.
2 will be replaced by {7 + 11 + 15 + 29 + 35 + 40}, i.e. 137.
29 will be replaced by {35 + 40}, i.e. 75.
1 will be replaced by {2 + 7 + 11 + 15 + 29 + 35 + 40}, i.e. 139.
7 will be replaced by {11 + 15 + 29 + 35 + 40}, i.e. 130.
15 will be replaced by {15 + 29 + 35 + 40}, i.e. 104.
40 will be replaced by 0 {as there is no node with a value greater than 40}.
35 will be replaced by {40}, i.e. 40.

You’re given an array 'arr' of size 'n' and an integer 'k'.

Your task is to split 'arr' into 'k' sub-arrays such that the maximum sum achieved from the 'k' subarrays formed must be the minimum possible.

A subarray is a contiguous part of the array.

Return the minimum possible value of the maximum sum obtained after splitting the array into 'k' partitions.

Example:

Input: ‘arr’ = [1, 1, 2] and ‘k’ = 2 

Output: 2

Explanation: If we want to make two subarrays, there are two possibilities: [[1], [1, 2]] and [[1, 1], [2]]. We can see that the maximum sum of any subarray is minimized in the second case. Hence, the answer is 2, which is the maximum sum of any subarray in [[1, 1], [2]].