# Amazon Interview Experience : SDE : Set 40

Company Name: Amazon

Job Role: SDE

Years of Experience Required: Fresher (0 Yrs.)

Drive: Off-Campus

## Preparation for Amazon

### Preparation

Topics: Data Structures and Algorithms

Duration: 3-5 months

Source of Preparation: Codechef,  Leetcode, Striver’s SDE sheet.

[BONUS]:

### Interview Rounds

Round 1 was a coding test where 2 coding questions were given.

• Sort an array of 0’s, 1’s, and 2’s: Given an array consisting of only 0s, 1s and 2s. Write a program to in-place sort the array without using inbuilt sort functions.
• Add two Linked List: Given the heads of two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.

Round 2: Technical Interview

Round 3: Technical Interview

• Rotten Oranges: You will be given an m x n grid, where each cell has the following values :
1. 2  –  represents a rotten orange
2. 1  –  represents a Fresh orange
3. 0  –  represents an Empty Cell

Every minute, if a Fresh Orange is adjacent to a Rotten Orange in 4-direction ( upward, downwards, right, and left ) it becomes Rotten. Return the minimum number of minutes required such that none of the cells has a Fresh Orange. If it’s not possible, return -1.
• Rod Cutting problem Dp: We are given a rod of size ‘N’. It can be cut into pieces. Each length of a piece has a particular price given by the price array. Our task is to find the maximum revenue that can be generated by selling the rod after cutting( if required) into pieces.

Round 4:Technical + Managerial

• He asked many situation-based questions
• Asked questions about my internships and then followed by a DSA question
• Serialize And Deserialize a Binary Tree: Design an algorithm to serialize and deserialize a binary tree. There is no restriction on how your serialization/deserialization algorithm should work. You just need to ensure that a binary tree can be serialized to a string and this string can be deserialized to the original tree structure.

Verdict: Selected