Product Engineer

The process of the COVID-19 vaccine has started in a special city structured like a binary tree. Ninja has been appointed as a doctor to do this vaccination. Some of the houses in the city are already vaccinated and Ninja wants to vaccinate the people in the remaining houses.

But the problem is that Ninja doesn’t remember the address of these remaining houses. However, he remembers that the houses that are still not vaccinated are at a ‘K’ distance from the last houses in the city. Ninja wants to find out how the number of these non-vaccinated houses.

Note :

The last house is similar to a leaf node in a binary tree and a house that is present at ‘K’ distance from the last house should be the direct ancestor of this last house.

For Example :

In this example :
2 is the direct ancestor of 4 and 5.
1 is the direct ancestor of 2, 3, 4, and 5.

You have been given an integer array/list(ARR) of size N which contains numbers from 0 to (N - 2). Each number is present at least once. That is, if N = 5, the array/list constitutes values ranging from 0 to 3 and among these, there is a single integer value that is present twice. You need to find and return that duplicate number present in the array.

Note :

Duplicate number is always present in the given array/list.

Given a 2D array of size Nx2 which contains a set of ‘N’ intervals. Each interval contains a starting point and an ending point. You need to find the size of the maximal set of mutually disjoint intervals.

Two sets [a,b] and [c,d] are disjoint intervals if there is no common point between these two intervals.

For example: [5,7] and [8,10] are disjoint intervals but the intervals [5,7] and [7,10] is not a disjoint interval as they have a common point, 7 in them.

Given a linked list having two pointers in each node. The first one points to the next node of the list, however, the other pointer is random and can point to any node of the list or null. The task is to create a deep copy of the given linked list and return its head. We will validate whether the linked list is a copy of the original linked list or not.

A deep copy of a Linked List means we do not copy the references of the nodes of the original Linked List rather for each node in the original Linked List, a new node is created.

For example,

Random pointers are shown in red and next pointers in black.

How does google auto correct works according to me

Flow Diagram of Book My Show

You have been given a long type array/list 'arr’ of size 'n’.

It represents an elevation map wherein 'arr[i]’ denotes the elevation of the 'ith' bar.

Print the total amount of rainwater that can be trapped in these elevations.

Note :

The width of each bar is the same and is equal to 1.

Example:

Input: ‘n’ = 6, ‘arr’ = [3, 0, 0, 2, 0, 4].

Output: 10

Explanation: Refer to the image for better comprehension:

Note :

You don't need to print anything. It has already been taken care of. Just implement the given function.

Four prisoners are given the opportunity of release and freedom if just one of them can work out the answer to a simple logic riddle. However, if they take part and one of them gives a wrong answer, or none of them can work out the answer at all, then their sentences will be doubled.

They are told that there are four hats. Two white and two black. Each man will have a hat placed on his head while blindfolded. When each man is wearing a hat the blindfolds will be removed. The prisoners will not be able to see their own hats and the only way they can work out what colour hat they are wearing will be from looking at the hats the other prisoners are wearing. All they have to do to win their freedom is for one of them to work out what colour hat he is wearing.

But there's a twist. To make it more interesting three prisoners stand in a line facing a brick wall. The prisoner at the back, A, stands on a box and can see both of the prisoners in front of him, B and C. Prisoner B stands on a smaller box and can only see prisoner C, who in turn can only see the wall. The fourth prisoner, D, stands on the other side of the wall and can see nothing of the other prisoners nor his own hat. They are not allowed to turn around, or converse in any way.

The prisoners are told that they have five minutes and to call out as soon as one of them thinks he knows for certain what colour hat he is wearing. But remember, if just one of them gets the answer wrong they will all have their sentences doubled.

Within the time allowed one prisoner calls out the right answer. Can you guess which one, what colour hat he is wearing and how he knew for sure?

You have been given a matrix of ‘N’ rows and ‘M’ columns filled up with integers. Find the minimum sum that can be obtained from a path which from cell (x,y) and ends at the top left corner (1,1).

From any cell in a row, we can move to the right, down or the down right diagonal cell. So from a particular cell (row, col), we can move to the following three cells:

Down: (row+1,col)
Right: (row, col+1)
Down right diagonal: (row+1, col+1)

You are given a non-negative integer ‘num’ in the form of a string and provided with an integer ‘k’.

You need to find the smallest integer possible by removing exactly ‘k’ digits from ‘num.’

Note :

‘num’ does not have leading zeros except when ‘num’ equals zero.

Example:

Input: ‘num’ = ‘141’ , ‘k’ = 1.

Output: ‘11’

Explanation: By removing only 1 digit from ‘num’, 3 numbers can be formed: 14, 11, and 41. Out of which 11 is the smallest number.

Note :

You don’t have to print anything. It has already been taken care of. Just implement the given function.