# Amazon Interview | Set 1

• Difficulty Level : Hard
• Last Updated : 13 Jun, 2019

Please find the details of my amazon interviews below.

Date of Interviews: 22nd August 2012

No of Rounds: 1 Written + 4 PI

Type of Interviews: Campus Interview for freshers

Written Test (Time): 90 Minutes

20 Objective Questions: Aptitude and basic C objective problems.

2 Subjective Questions:

II.               Some question based on sorting.

Interview Round 1(60-70 Minutes):

Technical Interview

Interview Round 2(50-60 Minutes):

Technical Interview

Question 1: There is a big file of words which is dynamically changing. We are continuously adding some words into it. How would you keep track of top 10 trending words at each moment?

Question 2: Write code for minHeapify() operation.

Question 3: Design a data structure for the following operations:

I.                Enqueue

II.               Dequeue

III.              Delete a given number(if it is present in the queue, else do nothing)

IV.               isNumberPresent

All these operations should take O(1) time.

Question 4: Write a function that returns the length of the longest leaf-to-leaf path in a binary tree.

Interview Round 3(60-70 Minutes):

Technical Interview

Question 1: There is a binary tree of size N. All nodes are numbered between 1-N(inclusive). There is a N*N integer matrix Arr[N][N], all elements are initialized to zero. So for all the nodes A and B, put Arr[A][B] = 1 if A is an ancestor of B (NOT just the immediate ancestor).

Question 3: There is a N*N integer matrix Arr[N][N]. From the row r and column c, we can go to any of the following three indices:

I.                Arr[ r+1 ][ c-1 ] (valid only if c-1>=0)

II.               Arr[ r+1 ][ c ]

III.              Arr[ r+1 ][ c+1 ] (valid only if c+1<=N-1)

So if we start at any column index on row 0, what is the largest sum of any of the paths till row N-1.

Interview Round 4(40-50 Minutes):

Bar Raiser Round

Interviewer asked HR Questions Initially, then a sort of puzzle.

Two robots land with their parachutes on an infinite one-dimensional number line. They both release their parachutes as soon as they land and start moving. They are allowed only to make use of the following functions.

I.                 moveLeft() // robot moves to left by 1 unit in 1 unit time

II.               moveRight() // robot moves to right by 1 unit in 1 unit time

III.              noOperation() // robot does not move and takes 1 unit time

IV.              onTopOfParachute() // returns true if the robot is standing on top of either of the parachute, else false

V.               didWeMeet() // returns true if the robot meets to the other robot, else false

Write a function in order to make the robots meet each other. Robots will be executing the same copy of this function.

HIRED!! 🙂