Loading…
Minimum Window Substring is a hard coding interview question covering strings, sliding window, hash maps — the kind asked at FAANG (Facebook/Meta, Apple, Amazon, Netflix, Google) and AI-first companies like Anthropic, OpenAI, and Nvidia.
Given strings s and t, return the smallest substring of s containing every character of t including duplicates, or "" if none exists. Example: s = "ADOBECODEBANC", t = "ABC" -> "BANC". Required: O(|s| + |t|) time.
Solution walkthrough on Pro
Upgrade to Pro to unlock the guided hints, the step-by-step walkthrough, solutions in Python, C++, Java, and Go, and complexity analysis.
What's inside this guide
Fully unlocked, no account needed — solutions, walkthroughs and follow-up answers included.
Or start the Study Plan — a week-by-week order for your loop, and week 1 is entirely free.
A full interview loop is more than one round. These are the others, each with what is on the site for it.