Dsa
Hashing
Medium
Longest Substring with K Unique Characters
Given a string and an integer K, find the length of the longest substring that contains at most K unique characters.
Input Format:
The first line contains the string. The second line contains the integer K (1 <= K <= length of string).
Output Format:
Print an integer representing the length of the longest substring.
Example:
Input:
araacek
2
Output:
5
Key concepts
hashingsliding windowsubstrings
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