Core Array and String Patterns: Two Pointers & Sliding Window

Apply the fast/slow pointer pattern for problems involving cycles and duplicates in arrays.

Solve problems requiring pointers moving from opposite ends (e.g., 2Sum, 3Sum, Container with Most Water).

Use the two-pointer approach to partition arrays (e.g., Dutch National Flag problem).

Implement variable-size sliding windows to find subarrays/substrings meeting specific criteria.

Solve substring problems using a sliding window combined with a frequency map.

Apply the sliding window deque method to find maximums/minimums in a fixed-size window.