I applied through a recruiter. The process took 2 months.

A recruiter reached out to me regarding the opportunity. After successfully clearing the Online Assessment (OA), I was invited to the Amazon Loop Interview process. The loop comprised four rounds:

• Two coding interviews (featuring two LeetCode Medium problems in the first round and one LeetCode Hard problem in the second)
• A behavioral interview focused extensively on Amazon's Leadership Principles
• A final interview with the Hiring Manager that included one coding problem and a High-Level Design (HLD) system design discussion

You are given a 2D grid representing a terrain map with three types of cells:

• 'T' - Radio tower (emits signals)
• 'M' - Mountain (blocks signals)
• '.' - Empty cell (signals pass through)

Each radio tower broadcasts signals in 4 cardinal directions (up, down, left, right). A signal travels in a straight line until it either:

• Hits a mountain (signal stops)
• Reaches the grid boundary (signal stops)

Your task: Determine which pairs of radio towers can communicate with each other. Two towers can communicate if a signal from one tower can reach the other tower.

Input Format grid = [ ['T', '.', '.', 'T'], ['.', 'M', '.', '.'], ['T', '.', '.', 'T'] ]

Example 1: Basic Line of Sight Input: T . . T . . . . T . . T

Signal Propagation: Tower (0,0) → → → reaches Tower (0,3) ✓ Tower (0,3) ↓ ↓ reaches Tower (2,3) ✓ Tower (2,0) → → → reaches Tower (2,3) ✓ Tower (0,0) ↓ ↓ reaches Tower (2,0) ✓

Output: [ ((0, 0), (0, 3)), # Top-left ↔ Top-right ((0, 3), (2, 3)), # Top-right ↔ Bottom-right ((2, 0), (2, 3)), # Bottom-left ↔ Bottom-right ((0, 0), (2, 0)) ]

Total communicating pairs: 4

Coding question were building a word game feature. Given a 2d from user tray and dictionary of valid words return all the words found by connecting adjavent cells board = o a a n e t a e i h k r i f l v

words = ["oath","pea","eat","rain"]

Output: ["oath","eat"]