THINK++ — Engineering Visualized

📖 LESSON

Two Pointer Technique

Two pointers is an optimization technique that uses two indices to traverse a collection, often reducing O(N²) solutions to O(N).

Opposite Ends

One pointer at the start, one at the end. (e.g., Palindrome check, 2-Sum in sorted array)

Slow & Fast

Both move at different speeds. (e.g., Linked List cycle detection)

Same Direction

Both move forward with varying gaps. (e.g., Remove duplicates)

Simulation Lab v2.0

Graph Engine Ready

Timeline

1/6

Edit Mode

Speed1000ms

Double-Click to Spawn

Drag Panels to Organize

💡 When to use?

Look for "Sorted Array", "Pairs", or "Subarrays" in the problem statement. These are common indicators that a two-pointer approach might work.

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