HardStringsAI interview only
Minimum Window Substring
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01 · Problem
Given two strings s and t of lengths m and n respectively, return the minimum window substring of s such that every character in t (including duplicates) is included in the window. If there is no such substring, return the empty string "".
The testcases will be generated such that the answer is unique.
02 · Examples
Example 01
Input
s = "ADOBECODEBANC", t = "ABC"
Output
"BANC"
The minimum window substring "BANC" (indices 9-12) contains all characters from t: 'A', 'B', and 'C'.
Example 02
Input
s = "a", t = "a"
Output
"a"
The entire string s is the smallest window that contains all characters of t.
03 · Constraints
- 01m == s.length
- 02n == t.length
- 031 <= m, n <= 105
- 04s and t consist of uppercase and lowercase English letters.
04 · Optimal complexity
- Time
- O(m + n)
- Space
- O(m + n)
05 · Two ways to work on it
Practice it alone or rehearse it as an interview.
Practice Mode gives you an editor and test runs, nothing else. AI Interview Mode puts a voice interviewer on the other side, adds a clock, and ends with a scored summary of the round.