SDE - 1

Given two numbers represented by linked lists. Your task is to find the multiplied list and return the head of the multiplied list.

The multiplied list is a linked list representation of the multiplication of two numbers.

You are given an array 'ARR' of 'N' positive integers. You need to find the length of the longest switching contiguous subarray.

An array is called Switching if all the elements at even indices are equal and all the elements at odd indices are also equal.

For Example :

If the given 'ARR' is [1, 4, 1, 4, 3, 2, 3, 0]. Then {1, 4, 1, 4}, {3, 2, 3}, {3, 0}, {0} are some of the switching subarrays. But {1, 4, 3}, {1, 4, 1, 4, 3, 2, 3} are not.

You are given a binary tree. For each level of the binary tree, find the floor value of the average of every node in the tree.

Example:-

For the given binary tree: [1, 2, 3, -1, -1, 4, 5, -1, -1, -1, -1]
Start Node: 3

    1
   / \
 2   3
      / \
     4  5

The answer should be [1,2,4] because level 1 has an average of 1(AVERAGE of 1), level 2 has an average of 2 (floor value) (AVERAGE of 2 and 3) and level 2 has an average of 4 (floor value) (AVERAGE of 4 and 5). 

You are given an arbitrary binary tree consisting of N nodes where each node is associated with a certain integer value from 1 to 9. Consider each root to leaf path as a number.

For example:

       1
      /  \
     2    3

The root to leaf path 1->2 represents the number 12.
The root to leaf path 1->3 represents the number 13.

Your task is to find the total sum of all the possible root to leaf paths.

In the above example,

The total sum of all the possible root to leaf paths is 12+13 = 25

Note:

The output may be very large, return the answer after taking modulus with (10^9+7).

You are given two binary search trees of integers having ‘N’ and ‘M’ nodes. Return an array that contains elements of both BST in sorted order.

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.

Given a Binary Search Tree (BST) and a range [min, max], remove all keys which are outside the given range. The modified tree should also be BST.