{Problem Number} -

Problem Link

• LeetCode | HackerRank

Difficulty

Easy | Medium | Hard

Topics

• Arrays
• Two Pointers
• ...

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Problem Summary

{One-liner description}

Key Insight

{The "aha" moment or trick that makes this problem solvable}

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Approaches

Approach 1: {Name} (Optimal)

Intuition: {Why this works}

Steps: 1. ... 2. ...

Complexity: Time O(...), Space O(...)

Approach 2: {Name} (Brute Force)

Complexity: Time O(...), Space O(...)

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Edge Cases

• Empty input
• Single element
• All same elements
• Negative numbers
• ...

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Similar Problems

• Problem Name
• Problem Name

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Notes

{Any additional learnings, mistakes made, or things to remember}