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How to Solve Most Frequent IDs Problem
Master the Most Frequent IDs LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
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Start Free for WindowsMedium#3092
LeetCode ProblemMost Frequent IDs
The problem involves tracking the frequency of IDs in a collection that changes over time. You have two integer arrays, nums and freq, of equal length n. Each element in nums represents an ID, and the corresponding element in freq indicates how many times that ID should be added to or removed from the collection at each step. Return an array ans of length n, where ans[i] represents the count of the most frequent ID in the collection after the ith step. If the collection is empty at any step, ans[i] should be 0 for that step.
ArrayHash TableHeap (Priority Queue)Ordered Set
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Problem Breakdown
Understanding the Most Frequent IDs Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
The problem involves tracking the frequency of IDs in a collection that changes over time. You have two integer arrays, nums and freq, of equal length n. Each element in nums represents an ID, and the corresponding element in freq indicates how many times that ID should be added to or removed from the collection at each step. Return an array ans of length n, where ans[i] represents the count of the most frequent ID in the collection after the ith step. If the collection is empty at any step, ans[i] should be 0 for that step.
MediumProblem #3092
LeetCodeMost Frequent IDs
Related Topics
ArrayHash TableHeap (Priority Queue)Ordered Set
How Phantom Code Helps
Get real-time assistance for Most Frequent IDs problems during coding interviews. Phantom Code provides instant solutions and explanations.
Examples
# Example 1
Input
nums = [2,3,2,1], freq = [3,2,-3,1]
Output
[3,3,2,2]
# Example 2
Input
nums = [5,5,3], freq = [2,-2,1]
Output
[2,0,1]
Constraints
1 <= nums.length == freq.length <= 105
1 <= nums[i] <= 105
-105 <= freq[i] <= 105
freq[i] != 0
The input is generated such that the occurrences of an ID will not be negative in any step.
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Solve Most Frequent IDs — The problem involves tracking the frequency of IDs in a collection that changes ...
Here's the optimal approach using Array:
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 Most Frequent IDs and using Phantom Code during coding interviews.
How does Phantom Code help me solve coding problems like Most Frequent IDs 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 Most Frequent IDs?
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 Most Frequent IDs?
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 Most Frequent IDs 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 Most Frequent IDs 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 Most Frequent IDs 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 Most Frequent IDs 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 Most Frequent IDs 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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