Solution: Longest Substring without Repeating Characters
Explore how to solve the longest substring without repeating characters problem by applying the sliding window technique. Learn to use a hash map for tracking characters and efficiently update the window to achieve an optimal linear-time solution.
Statement
Given a string, input_str, return the length of the longest substring without repeating characters.
Constraints:
-
input_str.length input_strconsists of English letters, digits, symbols, and spaces.
Solution
So far, you’ve probably brainstormed some approaches on how to solve this problem. Let’s explore some of these approaches and figure out which one to follow while considering time complexity and any implementation constraints.
Naive approach
The naive approach is to explore all possible substrings. For each substring, we check whether any character in it is repeated. After checking all the possible substrings, the substring with the longest length that satisfies the specified condition is returned.
The total time complexity of this solution is ...