A few years ago I solved 200 LeetCode problems and still froze on Mediums I hadn't seen. The breakthrough wasn't another hundred problems. It was a different loop. A problem asks for the longest substring with at most K distinct characters. You've solved sliding window before. Maximum sum subarray of size K, done. Longest substring without repeating characters, done. This third one stalls you. Twenty minutes pass. Discuss says sliding window. You'd already solved sliding window problems. The recognition didn't fire on this one. TL;DR: Practice volume builds memory of specific problems, not the recognition that fires before you start coding. The skill that transfers to unfamiliar interview mediums is identifying which technique applies from the problem's surface features. That recognition is what most LeetCode-style prep doesn't train, and that gap is what this post is about. What LeetCode actually does well LeetCode is the default coding interview prep platform for a reason.…