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Practice Count Distinct Numbers on Board

Master the Count Distinct Numbers on Board LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.

PhantomCodeAI generates complete solutions and debugging hints that you can use while explaining your approach, so you stay calm and in control.

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Easy#2549
LeetCode Problem

Count Distinct Numbers on Board

Initially the board contains n. On each of 10^9 days, for every number x currently present, add all integers i from 1 through n for which x modulo i is 1. Existing numbers remain on the board. Return the number of distinct integers present at the end.

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Problem Breakdown

Understanding the Count Distinct Numbers on Board Problem

Let's break down this LeetCode problem and understand what makes it challenging in interview settings.

Problem Statement

Initially the board contains n. On each of 10^9 days, for every number x currently present, add all integers i from 1 through n for which x modulo i is 1. Existing numbers remain on the board. Return the number of distinct integers present at the end.

Source: Count Distinct Numbers on Board on LeetCode. Use the original task for its coding environment and submissions.

EasyProblem #2549
LeetCode

Count Distinct Numbers on Board

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How PhantomCodeAI Helps

Get real-time assistance for Count Distinct Numbers on Board problems during coding interviews. PhantomCodeAI provides instant solutions and explanations.

Examples

# Example 1

Input
n = 5
Output
4

# Example 2

Input
n = 3
Output
2

Constraints

1 <= n <= 100

How PhantomCodeAI Helps with LeetCode Problems

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Undetectability Checklist

Run compatibility test before interviews
Use recommended Zoom version settings
Enable advanced screen capture options
Verify native desktop architecture
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Platform Compatibility

Zoom
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Google Meet
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HackerRank
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CodeSignal
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CoderPad
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Teams
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Undetectability and technical details

Our native desktop architecture avoids common detection vectors used by browser extensions. We provide a clear checklist so you can run basic checks and confirm the app will be invisible.

Platform compatibility and limitations

We work with Zoom, HackerRank, CodeSignal, CoderPad and other web-based platforms. Check the compatibility note and request a browser link if a specific desktop app is unsupported.

Frequently Asked Questions

Common questions about solving Count Distinct Numbers on Board and using PhantomCodeAI during coding interviews.

How does PhantomCodeAI help with LeetCode problems during a coding interview?
PhantomCodeAI reads the problem from a screenshot or listens to it via audio, then generates a complete solution with a step-by-step approach and time/space complexity, so you can focus on explaining your reasoning rather than getting stuck on implementation.
Which programming languages does PhantomCodeAI support?
11 languages including Python, Java, C++, JavaScript, TypeScript, Go, Rust, Ruby, Swift, Kotlin, and C#. Set a preferred language to get idiomatic solutions.
Does PhantomCodeAI work with HackerRank, CodeSignal, and CoderPad?
Yes — it works alongside LeetCode, HackerRank, CodeSignal, CoderPad, and HackerEarth, plus any browser-based coding environment.
Can PhantomCodeAI handle follow-up questions and modifications?
Yes. Capture the modified problem by screenshot or audio and get an updated solution within seconds, including new edge cases and optimizations.
Is PhantomCodeAI detectable during live interviews?
PhantomCodeAI runs as a native desktop overlay that does not appear in screen shares, recordings, or proctoring software, and works with Zoom, Google Meet, Microsoft Teams, and major coding platforms.
Should I still practice these problems on my own first?
Yes. The most durable preparation is solving problems unaided first, then using AI afterward to review your approach, complexity, and missed edge cases — use it to debrief and learn, not to skip the reps.

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