**Company Name:** Amazon

**Designation:** SDE1

**Experience:** 1.5 years

**Preparation for Amazon**

**Topics: **Data Structures and Algorithms

**Duration: **6 months

**Source of Preparation: **Leetcode, GFG, Striver’s SDE sheet.*Blind 75 Leetcode*

**Amazon Interview Rounds**

**Round 1:** There were two questions asked in the online round.

**Round 2:** Technical Interview

- Reverse a Linked List: Given the
*head*of a singly linked list, write a program to reverse the linked list, and return*the head pointer to the reversed list*. - Construct Binary Tree from inorder and preorder

**Round 3:** Technical Interview

- Length of the longest subarray with zero Sum: Given an array containing both positive and negative integers, we have to find the length of the longest subarray with the sum of all elements equal to zero.
- Flattening a Linked List: Given a Linked List of size N, where every node represents a sub-linked-list and contains two pointers:

(i) a next pointer to the next node,

(ii) a bottom pointer to a linked list where this node is head.

Each of the sub-linked-list is in sorted order.

Flatten the Link List such that all the nodes appear in a single level while maintaining the sorted order.

**Round 4:** Technical + Managerial Interview

- Why do you want to join amazon?
- Questions on my projects followed by a DSA question
- Minimum Path Sum In a Grid: We are given an “N*M” matrix of integers. We need to find a path from the top-left corner to the bottom-right corner of the matrix, such that there is a minimum cost past that we select. At every cell, we can move in only two directions: right and bottom. The cost of a path is given as the sum of the values of cells of the given matrix.

**Verdict:** Selected