You are given a 0-indexed array of strings words and a 2D array of integers queries.
Each query queries[i] = [li, ri] asks us to find the number of strings present at the indices ranging from li to ri (both inclusive) of words that start and end with a vowel.
Return an array ans of size queries.length, where ans[i] is the answer to the ith query.
Note that the vowel letters are 'a', 'e', 'i', 'o', and 'u'.
Examples
Example 1
Input: words = ["aba","bcb","ece","aa","e"], queries = [[0,2],[1,4],[1,1]]
Output: [2,3,0]
Explanation: The strings starting and ending with a vowel are "aba", "ece", "aa" and "e".
The answer to the query [0,2] is 2 (strings "aba" and "ece").
to query [1,4] is 3 (strings "ece", "aa", "e").
to query [1,1] is 0.
We return [2,3,0].
Example 2
Input: words = ["a","e","i"], queries = [[0,2],[0,1],[2,2]]
Output: [3,2,1]
Explanation: Every string satisfies the conditions, so we return [3,2,1].
Constraints
1 <= words.length <= 105
1 <= words[i].length <= 40
words[i] consists only of lowercase English letters.
sum(words[i].length) <= 3 * 105
1 <= queries.length <= 105
0 <= li <= ri < words.length
2559. Count Vowel Strings in Ranges
Medium
30 Points
Array
String
Prefix Sum
You are given a 0-indexed array of strings words and a 2D array of integers queries.
Each query queries[i] = [li, ri] asks us to find the number of strings present at the indices ranging from li to ri (both inclusive) of words that start and end with a vowel.
Return an array ans of size queries.length, where ans[i] is the answer to the ith query.
Note that the vowel letters are 'a', 'e', 'i', 'o', and 'u'.
Examples
Example 1
Input: words = ["aba","bcb","ece","aa","e"], queries = [[0,2],[1,4],[1,1]]
Output: [2,3,0]
Explanation: The strings starting and ending with a vowel are "aba", "ece", "aa" and "e".
The answer to the query [0,2] is 2 (strings "aba" and "ece").
to query [1,4] is 3 (strings "ece", "aa", "e").
to query [1,1] is 0.
We return [2,3,0].
Example 2
Input: words = ["a","e","i"], queries = [[0,2],[0,1],[2,2]]
Output: [3,2,1]
Explanation: Every string satisfies the conditions, so we return [3,2,1].
Constraints
1 <= words.length <= 105
1 <= words[i].length <= 40
words[i] consists only of lowercase English letters.
sum(words[i].length) <= 3 * 105
1 <= queries.length <= 105
0 <= li <= ri < words.length
Count Vowel Strings in Ranges - Practice Coding | SlaveCode