Count Beautiful Substrings II — LeetCode 2949 Python Solution

HardHash TableMathStringNumber TheoryPrefix Sum
Problem
#2949
Pattern
Prefix Sum
Reading time
2 min

The problem

You are given a string s and a positive integer k. Let vowels and consonants be the number of vowels and consonants in a string.

Example

Input
s = "baeyh", k = 2
Output
2
Explanation
There are 2 beautiful substrings in the given string.

Complexity

MeasureComplexity
TimeO(n)
SpaceO(n) auxiliary

Pattern: Prefix Sum

Precompute running totals once so any range query becomes a single subtraction. LeetCode 2949. Count Beautiful Substrings II is filed here because LeetCode tags it Prefix Sum, which is the vocabulary this hub collects.

The prefix sum guide has the Python template for the pattern and the 157 LeetCode problems that use it.

Related problems

Frequently asked questions

How hard is LeetCode 2949. Count Beautiful Substrings II?
LeetCode 2949. Count Beautiful Substrings II is rated Hard on LeetCode.
What is the time complexity of LeetCode 2949. Count Beautiful Substrings II?
The Python solution on this page runs in O(n).
What is the space complexity of LeetCode 2949. Count Beautiful Substrings II?
The Python solution on this page uses O(n) auxiliary space.
What topics does LeetCode 2949. Count Beautiful Substrings II cover?
LeetCode 2949. Count Beautiful Substrings II is tagged Hash Table, Math, String, Number Theory and Prefix Sum on LeetCode.

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