Round 1 - (DSA)

https://leetcode.com/discuss/post/7280587/zeta-sde-2-2025-by-anonymous_user-xc23/

Round 2 - (LLD) 90 Mins

• first 15 minutes he wasted asking about my current work and feature i developed in my current company.
• need to solved first core requirements if time permits then go for additional requirements.
• he mentioned he wants me to show some running functionality of code
• i was able to complete core funtionalities but time ran out and i couldn't show my code was running.
• if you want me to show running code why would you waste initial 15 mins of interview asking about my work it's LLD round not HM.
• i completed proper DAOs, Models, Services, but couldn't write main class to demonstrate

NOTE: If you want i could upload the code i wrote in interview

if you ask me, interview was good apart from the driver code i couldn't write to demonstrate but i explained my flow and approach. Could've been yes

Exact question was -

Caller identification and Spam blocking application - Requirements Document

Problem Statement

Design a caller identification and spam blocking application that helps users identify unknown callers, block spam calls, and manage their calling experience. The system should provide real-time caller information during incoming calls and maintain a collaborative spam detection network.

Functional Requirements

Core Features

User Registration & Profile Management

• Users can register using phone number.
• Users can create and update their profile.
• Sync phone contacts with the application

Caller Identification

• Identify incoming calls from unknown numbers in real-time
• Display caller's name and additional information if available
• Work for both saved and unsaved contacts
• Display verification status of callers

Spam Detection & Blocking

• Automatically identify potential spam calls
• Allow users to mark numbers as spam
• Block calls from spam numbers
• Community-based spam reporting
• Support for different spam categories (telemarketing, scam, robocall, harassment)

Additional Features

Contact

• Users can control their privacy settings.(PRIVATE, PUBLIC)
• Support for subscription tiers (FREE, PREMIUM, BUSINESS)
• Search for people by name or phone number
• View profiles of other users (respecting privacy settings)

Statistics on Blocked Calls

• Comprehensive call analytics
• Spam blocking effectiveness metrics
• User activity statistics

Call History

• Maintain enhanced call logs with caller information
• Tag calls (personal, business, spam, etc.)
• Search through call history
• Call duration tracking and statistics
• Daily/weekly/monthly analytics

Spam

• Spam confidence scoring system

SMS Spam Filtering

• Content-based spam detection
• Pattern matching for promotional messages
• Keyword analysis for suspicious content
• Filter actions: allow, mark suspicious, quarantine, block

Number Lookup/Reverse Search

• Comprehensive phone number analysis
• Reverse name search functionality
• Phone number validation and formatting
• Carrier and region information

Business Caller Identification

• Business name, category, and description
• Verified business status
• Company address and website information
• Business directory