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Longest Unique Message Substring

Medium

Coding

Asked at 1 company1StringsHash TablesTwo Pointers

Also asked at

Problem

In Meta Messenger, you are given a string s representing a message. Return the length of the longest substring that contains no repeated characters.

A substring must be contiguous. You should solve this efficiently for large inputs.

Formal Specification

Input: A string s
Output: An integer representing the maximum length of a substring of s with all unique characters

Examples

Example 1

Input: s = "abcabcbb"
Output: 3
Explanation: The longest substring without repeating characters is "abc", which has length 3.

Example 2

Input: s = "bbbbb"
Output: 1
Explanation: Every substring longer than length 1 repeats the character "b".

Example 3

Input: s = "pwwkew"
Output: 3
Explanation: One valid longest substring is "wke". "pwke" is not valid because it is not contiguous.

Constraints

0 <= len(s) <= 10^5
s may contain letters, digits, symbols, and spaces
Return only the maximum length, not the substring itself

Examples

Example 1

Inputs = "abcabcbb"Output3WhyThe longest substring with all distinct characters is `"abc"`.

Example 2

Inputs = "bbbbb"Output1WhyOnly one unique character can appear in any valid substring, so the answer is 1.

Example 3

Inputs = "pwwkew"Output3Why`"wke"` is a longest valid substring. Longer candidates contain repeated characters or are not contiguous.

Constraints

0 <= len(s) <= 10^5
s consists of printable characters, including letters, digits, symbols, and spaces
Return the length of the longest valid substring

Function Signature

def length_of_longest_substring(s):

Problem

In Meta Messenger, you are given a string s representing a message. Return the length of the longest substring that contains no repeated characters.

A substring must be contiguous. You should solve this efficiently for large inputs.

Formal Specification

Input: A string s
Output: An integer representing the maximum length of a substring of s with all unique characters

Examples

Example 1

Input: s = "abcabcbb"
Output: 3
Explanation: The longest substring without repeating characters is "abc", which has length 3.

Example 2

Input: s = "bbbbb"
Output: 1
Explanation: Every substring longer than length 1 repeats the character "b".

Example 3

Input: s = "pwwkew"
Output: 3
Explanation: One valid longest substring is "wke". "pwke" is not valid because it is not contiguous.

Constraints

0 <= len(s) <= 10^5
s may contain letters, digits, symbols, and spaces
Return only the maximum length, not the substring itself

Examples

Example 1

Inputs = "abcabcbb"Output3WhyThe longest substring with all distinct characters is `"abc"`.

Example 2

Inputs = "bbbbb"Output1WhyOnly one unique character can appear in any valid substring, so the answer is 1.

Example 3

Inputs = "pwwkew"Output3Why`"wke"` is a longest valid substring. Longer candidates contain repeated characters or are not contiguous.

Constraints

0 <= len(s) <= 10^5
s consists of printable characters, including letters, digits, symbols, and spaces
Return the length of the longest valid substring

Function Signature

def length_of_longest_substring(s):

Practice Python

Python 3.10

Open on desktop for the full Python editor with syntax highlighting and autocomplete.

Up next

Longest Unique Messenger SubstringMedium

Longest Unique Message SubstringMedium

Longest Unique Messenger SubstringMedium

Next question

Longest Unique Message Substring

Medium

Coding

Asked at 1 company1StringsHash TablesTwo Pointers

Also asked at

Problem

In Meta Messenger, you are given a string s representing a message. Return the length of the longest substring that contains no repeated characters.

A substring must be contiguous. You should solve this efficiently for large inputs.

Formal Specification

Input: A string s
Output: An integer representing the maximum length of a substring of s with all unique characters

Examples

Example 1

Input: s = "abcabcbb"
Output: 3
Explanation: The longest substring without repeating characters is "abc", which has length 3.

Example 2

Input: s = "bbbbb"
Output: 1
Explanation: Every substring longer than length 1 repeats the character "b".

Example 3

Input: s = "pwwkew"
Output: 3
Explanation: One valid longest substring is "wke". "pwke" is not valid because it is not contiguous.

Constraints

0 <= len(s) <= 10^5
s may contain letters, digits, symbols, and spaces
Return only the maximum length, not the substring itself

Examples

Example 1

Inputs = "abcabcbb"Output3WhyThe longest substring with all distinct characters is `"abc"`.

Example 2

Inputs = "bbbbb"Output1WhyOnly one unique character can appear in any valid substring, so the answer is 1.

Example 3

Inputs = "pwwkew"Output3Why`"wke"` is a longest valid substring. Longer candidates contain repeated characters or are not contiguous.

Constraints

0 <= len(s) <= 10^5
s consists of printable characters, including letters, digits, symbols, and spaces
Return the length of the longest valid substring

Function Signature

def length_of_longest_substring(s):

Problem

In Meta Messenger, you are given a string s representing a message. Return the length of the longest substring that contains no repeated characters.

A substring must be contiguous. You should solve this efficiently for large inputs.

Formal Specification

Input: A string s
Output: An integer representing the maximum length of a substring of s with all unique characters

Examples

Example 1

Input: s = "abcabcbb"
Output: 3
Explanation: The longest substring without repeating characters is "abc", which has length 3.

Example 2

Input: s = "bbbbb"
Output: 1
Explanation: Every substring longer than length 1 repeats the character "b".

Example 3

Input: s = "pwwkew"
Output: 3
Explanation: One valid longest substring is "wke". "pwke" is not valid because it is not contiguous.

Constraints

0 <= len(s) <= 10^5
s may contain letters, digits, symbols, and spaces
Return only the maximum length, not the substring itself

Examples

Example 1

Inputs = "abcabcbb"Output3WhyThe longest substring with all distinct characters is `"abc"`.

Example 2

Inputs = "bbbbb"Output1WhyOnly one unique character can appear in any valid substring, so the answer is 1.

Example 3

Inputs = "pwwkew"Output3Why`"wke"` is a longest valid substring. Longer candidates contain repeated characters or are not contiguous.

Constraints

0 <= len(s) <= 10^5
s consists of printable characters, including letters, digits, symbols, and spaces
Return the length of the longest valid substring

Function Signature

def length_of_longest_substring(s):

Practice Python

Python 3.10

Open on desktop for the full Python editor with syntax highlighting and autocomplete.

Up next

Longest Unique Messenger SubstringMedium

Longest Unique Message SubstringMedium

Longest Unique Messenger SubstringMedium

Next question