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How to Solve Count Number of Trapezoids II Problem
Master the Count Number of Trapezoids II LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
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Start Free for WindowsHard#3625
LeetCode ProblemCount Number of Trapezoids II
You are given a 2D integer array points where points[i] = [xi, yi] represents the coordinates of the ith point on the Cartesian plane. Return the number of unique trapezoids that can be formed by choosing any four distinct points from points. A trapezoid is a convex quadrilateral with at least one pair of parallel sides. Two lines are parallel if and only if they have the same slope.
ArrayHash TableMathGeometry
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Problem Breakdown
Understanding the Count Number of Trapezoids II Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
You are given a 2D integer array points where points[i] = [xi, yi] represents the coordinates of the ith point on the Cartesian plane. Return the number of unique trapezoids that can be formed by choosing any four distinct points from points. A trapezoid is a convex quadrilateral with at least one pair of parallel sides. Two lines are parallel if and only if they have the same slope.
HardProblem #3625
LeetCodeCount Number of Trapezoids II
Related Topics
ArrayHash TableMathGeometry
How Phantom Code Helps
Get real-time assistance for Count Number of Trapezoids II problems during coding interviews. Phantom Code provides instant solutions and explanations.
Examples
# Example 1
Input
points = [[-3,2],[3,0],[2,3],[3,2],[2,-3]]
Output
2
# Example 2
Input
points = [[0,0],[1,0],[0,1],[2,1]]
Output
1
Constraints
4 <= points.length <= 500
–1000 <= xi, yi <= 1000
All points are pairwise distinct.
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Solve Count Number of Trapezoids II — You are given a 2D integer array points where points[i] = [xi, yi] represents th...
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 Count Number of Trapezoids II and using Phantom Code during coding interviews.
How does Phantom Code help me solve coding problems like Count Number of Trapezoids II 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 Count Number of Trapezoids II?
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 Count Number of Trapezoids II?
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 Count Number of Trapezoids II 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 Count Number of Trapezoids II 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 Count Number of Trapezoids II 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 Count Number of Trapezoids II 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 Count Number of Trapezoids II 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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