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How to Solve Find the Child Who Has the Ball After K Seconds Problem
Master the Find the Child Who Has the Ball After K Seconds LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
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Start Free for WindowsEasy#3178
LeetCode ProblemFind the Child Who Has the Ball After K Seconds
You are given two positive integers n and k. There are n children numbered from 0 to n - 1 standing in a queue in order from left to right. Initially, child 0 holds a ball and the direction of passing the ball is towards the right direction. After each second, the child holding the ball passes it to the child next to them. Once the ball reaches either end of the line, i.e. child 0 or child n - 1, the direction of passing is reversed. Return the number of the child who receives the ball after k seconds. Example 1: Example 2: Example 3: Constraints: Note: This question is the same as 2582: Pass the Pillow.
MathSimulation
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Problem Breakdown
Understanding the Find the Child Who Has the Ball After K Seconds Problem
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Problem Statement
You are given two positive integers n and k. There are n children numbered from 0 to n - 1 standing in a queue in order from left to right. Initially, child 0 holds a ball and the direction of passing the ball is towards the right direction. After each second, the child holding the ball passes it to the child next to them. Once the ball reaches either end of the line, i.e. child 0 or child n - 1, the direction of passing is reversed. Return the number of the child who receives the ball after k seconds. Example 1: Example 2: Example 3: Constraints: Note: This question is the same as 2582: Pass the Pillow.
EasyProblem #3178
LeetCodeFind the Child Who Has the Ball After K Seconds
Related Topics
MathSimulation
How Phantom Code Helps
Get real-time assistance for Find the Child Who Has the Ball After K Seconds problems during coding interviews. Phantom Code provides instant solutions and explanations.
Examples
# Example 1
Input
n = 3, k = 5
Output
1
# Example 2
Input
n = 5, k = 6
Output
2
# Example 3
Input
n = 4, k = 2
Output
2
Constraints
2 <= n <= 50
1 <= k <= 50
How Phantom Code Helps with LeetCode Problems
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Solve Find the Child Who Has the Ball After K Seconds — You are given two positive integers n and k. There are n children numbered from ...
Here's the optimal approach using Math:
def solve(input):
# Optimal O(n) solution
return result
Time: O(n) | Space: O(n)
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Frequently Asked Questions
Common questions about solving Find the Child Who Has the Ball After K Seconds and using Phantom Code during coding interviews.
How does Phantom Code help me solve coding problems like Find the Child Who Has the Ball After K Seconds during interviews?
Phantom Code generates complete solutions instantly with proper complexity analysis, letting you focus on explaining your approach and demonstrating problem-solving skills rather than getting stuck on implementation details during high-pressure situations.
What if the interviewer asks follow-up questions or modifications to problems like Find the Child Who Has the Ball After K Seconds?
Phantom Code adapts in real-time. Screenshot the modified problem or use audio mode to capture the interviewer's follow-up, and get an updated solution within seconds — including edge cases and optimizations.
Can Phantom Code help me communicate my solution for problems like Find the Child Who Has the Ball After K Seconds?
Yes. Phantom Code provides step-by-step approach explanations with 3 progressive thoughts, so you can walk through your solution naturally. It also provides time and space complexity analysis to discuss trade-offs.
How does Phantom Code assist with different programming languages for Find the Child Who Has the Ball After K Seconds type problems?
Phantom Code supports 11 programming languages including Python, Java, C++, JavaScript, TypeScript, Go, Rust, Ruby, Swift, Kotlin, and C#. Set your preferred language and get idiomatic solutions.
What coding mistakes does Phantom Code help me avoid during Find the Child Who Has the Ball After K Seconds interviews?
Phantom Code catches common mistakes like off-by-one errors, missing edge cases, incorrect base conditions, and suboptimal approaches. It provides clean, well-structured code that handles all edge cases.
Is Phantom Code detectable when solving problems like Find the Child Who Has the Ball After K Seconds during live interviews?
No. Phantom Code runs as an invisible desktop overlay that doesn't appear in screen shares, recordings, or proctoring software. It works with Zoom, HackerRank, CodeSignal, CoderPad, and all major platforms.
How does Phantom Code help when I'm struggling with Find the Child Who Has the Ball After K Seconds style questions under pressure?
The AI provides structured guidance: first the approach (what algorithm/data structure to use and why), then the implementation with clean code, and finally complexity analysis. This helps you think clearly even under pressure.
Does Phantom Code work for the coding platforms used in Find the Child Who Has the Ball After K Seconds interviews?
Yes. Phantom Code works with all major coding platforms including LeetCode, HackerRank, CodeSignal, CoderPad, HackerEarth, and any browser-based coding environment.
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