Count vowel-only substrings with all vowels
Problem: Count Vowel-Only Substrings with All Vowels
Given a lowercase English string s, your task is to return the total number of contiguous substrings that satisfy two conditions:
- The substring must consist only of vowels from the set
{a, e, i, o, u}. - The substring must contain each of the five vowels (
a, e, i, o, u) at least once.
Constraints
1 <= |s| <= 200000
Performance Requirements
- Design an
O(n)time complexity solution. - Utilize
O(1)extra space (beyond the input string).
Discussion Points
Be prepared to explain:
- How your solution handles consonants that break potential vowel-only windows.
- How your solution accounts for repeated vowels within a valid window.
- How your solution efficiently processes long runs of vowels.
Deliverables
- Provide working code for your solution.
- Analyze the time and space complexity of your approach.
AI interview prep
Core dilemma
The central engineering conflict is efficiently counting *all* valid substrings (those containing only vowels and all five unique vowels) in O(N) time and O(1) space. The challenge lies in correctly identifying and summing up all valid sub-windows that end at a given right pointer, rather than just finding the first or longest valid window.
3 tradeoffs and 3 stress tests locked
Interview prep
Unlock the interviewer X-Ray rubric, tradeoff matrix, stress tests, clarifying questions, and key concepts.
Count vowel-only substrings with all vowels
Problem: Count Vowel-Only Substrings with All Vowels
Given a lowercase English string s, your task is to return the total number of contiguous substrings that satisfy two conditions:
- The substring must consist only of vowels from the set
{a, e, i, o, u}. - The substring must contain each of the five vowels (
a, e, i, o, u) at least once.
Constraints
1 <= |s| <= 200000
Performance Requirements
- Design an
O(n)time complexity solution. - Utilize
O(1)extra space (beyond the input string).
Discussion Points
Be prepared to explain:
- How your solution handles consonants that break potential vowel-only windows.
- How your solution accounts for repeated vowels within a valid window.
- How your solution efficiently processes long runs of vowels.
Deliverables
- Provide working code for your solution.
- Analyze the time and space complexity of your approach.