SDE - 1

You are given a singly linked list of integers.

Your task is to swap every two adjacent nodes, and return the head of the modified, linked list.

For Example:

We have a linked list 1->2->3->4->5->6->7 and so on. You are supposed to swap pairs of a linked list like swap (1,2), (3,4), (5,6), and so on.

Note:

1. You may not modify the data in the list’s nodes; only nodes themselves may be changed. Because imagine a case where a node contains many fields, so there will be too much unnecessary swap.

2. If a pair of a node does not exist, then leave the node as it is.

You have been given a binary search tree of integers with ‘N’ nodes and a target integer value ‘K’. Your task is to find the closest element to the target ‘K’ in the given binary search tree.

A node in BST is said to be the closest to the target if its absolute difference with the given target value ‘K’ is minimum. In the case of more than one closest element, return the element with a minimum value.

A binary search tree (BST) is a binary tree data structure with the following properties.

• The left subtree of a node contains only nodes with data less than the node’s data.

• The right subtree of a node contains only nodes with data greater than the node’s data.

• Both the left and right subtrees must also be binary search trees.

For Example:

For the given BST and target value ‘K’ =  32, the closest element is 30 as the absolute difference between 30 and 32 (|32 - 30|) is the minimum among all other possible node-target pairs.

What is Kernel and write its main functions?