ThoughSpot Interview Experience/Question - MTS2,3

Summary

Interviewee was asked to write a C++ program to determine service deployment order based on dependencies, ensuring no cycles and proper batching.

How it went

Hi everyone! I recently interviewed with the ThoughtSpot Orion Team and wanted to share a specific question I was asked. The team emphasized that this problem is very representative of their daily work on the orchestration layer. If you’re preparing for a role with them, I highly recommend practicing this one.

The Question:
You are given a root directory called:

/services

Inside this directory, each subdirectory represents a service.

Example:

/services
    /Auth
        config.txt
    /Billing
        config.txt
    /User
        config.txt
    /Database
        config.txt

📄 Config File Format

Each service contains a file config.txt.

The file contains exactly one line in this format:

depends=ServiceA,ServiceB,ServiceC

If there are no dependencies:

depends=

🎯 Requirements

Write a C++ program that:

Scans all service folders inside /services.
Parses each config.txt.
Determines the correct deployment order.
Ensures:
- A service is deployed only after all services listed in its depends line are deployed.
- Services that have no remaining unmet dependencies can be deployed in parallel.
Outputs deployment batches.
Detects cyclic dependencies and prints:

Error: Cycle detected. Deployment not possible.

✅ Example

Folder Structure

Auth     → depends=Database
Billing  → depends=Auth
User     → depends=Auth
Database → depends=

Expected Output

Batch 1: Database
Batch 2: Auth
Batch 3: Billing User

Questions asked (1)

01
Service Deployment Order Based on Dependencies
Data Structures & Algorithms · Hard
You are given a root directory called /services. Inside this directory, each subdirectory represents a service. Each service contains a file config.txt, which lists its dependencies in the format:
```
depends=ServiceA,ServiceB,ServiceC
```
If there are no dependencies, the file will contain just:
```
depends=
```
Your task is to write a C++ program that:
- Scans all service folders inside /services.
- Parses each config.txt.
- Determines the correct deployment order such that a service is deployed only after all its dependencies are deployed.
- Groups services that can be deployed in parallel into batches.
- Detects cyclic dependencies and returns an error message if any cycle exists.
Example Folder Structure:
```
Auth     → depends=Database
Billing  → depends=Auth
User     → depends=Auth
Database → depends=
```
Expected Output:
```
Batch 1: Database
Batch 2: Auth
Batch 3: Billing User
```
In case of a cycle, output:
```
Error: Cycle detected. Deployment not possible.
```