Product Engineer

In the Kingdom of Arborvale, there is a hierarchical system of nobles arranged in a tree-like structure. The kingdom has 'n' nobles, each assigned a unique number from 1 to 'n'. At the top is the King, who is the root of the structure.

Each noble has a parent, except for the King. Some nobles are loyal and respect their ancestors, while others are rebellious.

You are tasked with restoring peace by removing rebellious nobles according to a specific process:

1)You must select a noble to remove who meets all of the following criteria:

I) Is not the King (i.e., is not the root).
II) Is rebellious (does not respect their parent).
III) Has no children who are loyal (i.e., all of its children are also rebellious, or it has no children at all).

2)If multiple nobles meet these criteria, you must select the one with the smallest number.

3)When a noble is removed, all of its children are immediately re-assigned to its parent. This does not affect any other nobles in the current step but may influence future removals.

4)The process continues, selecting and removing one noble at a time, until no nobles are left that meet the removal criteria.

Your task is to determine the order in which the rebellious nobles will be removed.

In the city of Gridopolis, the layout is a 2xN grid of blocks. Each block can be either open for passage (.) or closed for construction (x).

A neighborhood is defined as a set of open blocks that are all connected. Two open blocks are connected if you can travel from one to the other by moving between adjacent blocks, either horizontally or vertically.

You are given that the initial city grid contains at most one connected neighborhood.

Your task is to identify and count the number of critical blocks. A critical block is an open block that, if it were to be closed for construction (changed from . to x), would cause the city to split into exactly 3 separate neighborhoods.

You are given a maze consisting of N cells numbered from 0 to N - 1 and an array ‘arr’ of N integers in which arr[i] contains the cell number that can be reached from ‘i’th cell in one step. You are supposed to find the length of the largest cycle in the maze, given that each cell has less than or equal to 1 exit but can have multiple entry points.

Note:

The maze may contain self-cycles.
arr[i] = -1 means the ‘i’th cell doesn’t have an exit.

Questions based on tension and the laws of motion on an inclined plane.

Questions based on collisions.

It was an output-based question, so a line-by-line dry run was used to solve it.

Question regarding process management and process execution.

What is normalization? (Learn)

What is a deadlock and its necessary conditions? (Learn)

You are given a world map represented as a generic M-ary Tree with 'N' uniquely named nodes. Your task is to implement a locking system with three distinct operations: Lock, Unlock, and Upgrade.

The system must process a series of queries, each representing one of these operations, and determine if the operation can be performed successfully.

The operations are defined as follows, where X is the name of a node and uid is the ID of a user:

1) Lock(X, uid): This operation attempts to grant an exclusive lock on the node X for the user uid. A lock can only be granted if:
  I) The node X is not already locked.
  II) No ancestor of X is locked.
  III) No descendant of X is locked.

2) Unlock(X, uid): This operation releases a lock on node X. It can only be performed if:
  I) The node X is currently locked.
  II) The lock on X is held by the same user uid.

3) UpgradeLock(X, uid): This operation allows a user uid to lock an ancestor node X by atomically unlocking all of its descendants that they have locked. An upgrade is possible only if:
  I) The node X is not currently locked.
  II) X has at least one locked descendant.
  III) All locked descendants of X are locked by the same user uid.
  IV) If successful, X becomes locked by uid, and all its previously locked descendants become unlocked.

Key Differences Between GET and POST Methods. (Learn)

Given an array ‘ARR’ of ‘N’ integers, where all the elements occur an even number of times and only one number occurs an odd number of times.

Find and return the number which occurs an odd number of times.

For example:

'N' = 5, 'ARR' = [1, 2, 3, 2, 3]
Output: 1

Except for number 1, all numbers occur an even number of times.

You are given a 2-dimensional array/list having N rows and M columns, which is filled with ones(1) and zeroes(0). 1 signifies land, and 0 signifies water.

A cell is said to be connected to another cell, if one cell lies immediately next to the other cell, in any of the eight directions (two vertical, two horizontal, and four diagonals).

A group of connected cells having value 1 is called an island. Your task is to find the number of such islands present in the matrix.

Optimize the code submitted in the 3rd round and implement the lock method in the tree-of-space question so that it works on a multi-core machine without using built-in mutexes, semaphores, or lock functions. The lock should be granular.

You are designing a new programming language and have full control over it. Now, in the compiler or runtime environment of this language, you need to set up a garbage collector. How would you design a garbage collector for it?

What is a Process Control Block, and how does the heap store data? (Learn)

What is Redis caching?

What is encryption?

You have 3 wires with unusual and non-uniform shapes and sizes. Each wire burns completely in 10 minutes, but the rate of burning is not constant.

With 3 wires, how can you measure 15 minutes?

If you have only 2 wires, how can you measure 15 minutes?

You have 25 cars and a racetrack where only 5 cars can race at a time. You don’t know the exact speed of each car; you only know the relative speeds of the 5 cars you race together at a time. Determine the top 3 fastest cars among the 25.