50 LeetCode Patterns That Cover 90% of Interviews

The biggest mistake candidates make is grinding 500+ LeetCode problems without a strategy. You do not need to solve every problem on the platform. You need to recognize patterns. When you see a new problem in an interview, your brain should instantly map it to a known pattern and adapt the template. This guide covers the 50 most important patterns grouped into categories, with the exact problems you should solve to internalize each one. Start with the foundations. Two Pointers is the single most versatile pattern. It applies to sorted arrays, linked lists, and string problems. The classic setup: one pointer at the start, one at the end, moving inward based on a condition. Use it for pair sum problems, removing duplicates, and container with most water.