Code RoomMinimum window substring
HardPrep Room Coding #890

Minimum window substring

CodingAlgorithms & data structuresSenior–Staff~35 min

Given strings s and t, return the shortest substring of s that contains every character of t including multiplicities. If no such substring exists, return the empty string. If multiple shortest windows exist, return the one that starts earliest. Constraints: 1 <= len(s), len(t) <= 10^4, both consist of uppercase and lowercase English letters.

Implement
min_window_substring(s: str, t: str) → str
Examples
in["ADOBECODEBANC","ABC"]out"BANC"
What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

0:00 of about 35 min
InputExpectedGot
["ADOBECODEBANC","ABC"]"BANC"not run yetsample