Multiple Pointers

Concepts covered: pyTwoPointer

Pointers from Both Ends The most common pattern uses one pointer at the start and one at the end, moving them toward each other. This efficiently solves problems like finding pairs, checking palindromes, and partitioning arrays: Because the list is sorted, we know that if the sum is too small, we need a larger left value. If too large, we need a smaller right value. This lets us eliminate many possibilities with each comparison. Palindrome Check Checking if a string is a palindrome is a classic two-pointer problem. Compare characters from both ends, moving inward: Fast and Slow Pointers Another pattern uses two pointers moving at different speeds. The fast pointer explores ahead while the slow pointer tracks a different position. This solves problems like removing duplicates in-place: Thre

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