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How to Solve Diagonal Traverse II Problem
Master the Diagonal Traverse II LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
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Medium#1424
LeetCode ProblemDiagonal Traverse II
Given a 2D integer array nums, return all elements of nums in diagonal order as shown in the below images.
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Problem Breakdown
Understanding the Diagonal Traverse II Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
Given a 2D integer array nums, return all elements of nums in diagonal order as shown in the below images.
MediumProblem #1424
LeetCodeDiagonal Traverse II
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How PhantomCodeAI Helps
Get real-time assistance for Diagonal Traverse II problems during coding interviews. PhantomCodeAI provides instant solutions and explanations.
Examples
# Example 1
Input
nums = [[1,2,3],[4,5,6],[7,8,9]]
Output
[1,4,2,7,5,3,8,6,9]
# Example 2
Input
nums = [[1,2,3,4,5],[6,7],[8],[9,10,11],[12,13,14,15,16]]
Output
[1,6,2,8,7,3,9,4,12,10,5,13,11,14,15,16]
Constraints
1 <= nums.length <= 105
1 <= nums[i].length <= 105
1 <= sum(nums[i].length) <= 105
1 <= nums[i][j] <= 105
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Solve Diagonal Traverse II — Given a 2D integer array nums, return all elements of nums in diagonal order as ...
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 Diagonal Traverse II 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.
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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?
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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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