SDE 2 iOS Role - Tesco

Hi guys, I had an interview with Tesco Bangalore, under payroll for another company. Basically Ill be paid by the third party company but Ill be working for Tesco. After 6 months, based on my performance Ill be a FTE for Tesco. This was communicated by the HR prior

My experience - 8 years.
Current role - Senior Software Engineer - iOS (Laid off)
Current CTC - 38.7 LPA
Offer Tesco was offering - 42 LPA
Location - Bangalore.

1. First round - Payroll company
A complete technical round with the company that runs the payroll.
- iOS Technical question
- Questions related to ARC
- Questions from SwiftUI, Combine, async await
- Architecture question
- How project is architectured in swiftUI
- How API calls are made, How network layer is constructed
- How Business logic is handled etc.
- Coding question - Cannot recollect that solved 0(n) and later was asked to solve in 0(log n). Did it

2. Second round - Tesco Round
A complete technical round, this was actually the first round as per TESCO.
- Coding question - Given an array of array of strings, find the strings with hashtags in that.

Input: [["Hi","My name is #XYZAABC"],["How are you doing", "This is first post #FirstPost"]] Output: ["#XYZAABC", "#FirstPost"]

Solved using O(n log n) asked to solve using 0(n). Didnt get time but gave a solution.
- iOS Technical questions
- SOLID principles
- Asked to identify issues with subclassing and violation on which rule in SOLID and asked to solve it
- Architechtures and Patterns used
- Combine, High order functions
- ARC, State management
- Given code of the GCD threads, asked to predict output
- Actor vs Classed, whats data isolation in Actor.

3. Third Round - System Design Tesc round
This was the last round and it was a HLD and LLD round
- The interview started a bit different than other rounds, later I understood that it was done that way to understand the candidate in pressure sitaution and Im fine with it.
- Given a feature, Categories have SubCategories, A Subcategory can either have Subcategory or a product.
- So Category has Subcategory, SubCategory has another Subcategory or Product but not both.
- Asked for an high level design and then low level design.
- I was not clear that the interview was expecting code as well and I was just focusing on the high level part and later I understood but it was too late
- So the solution was not complete but the interview discussed on upcoming steps and solutions etc. - Final verdict: Couldnt pass the System design round as it was not satisfactory for the interviewer. Hence got rejected.