LeetCode in Kotlin
2062. Count Vowel Substrings of a String
Easy
A substring is a contiguous (non-empty) sequence of characters within a string.
A vowel substring is a substring that only consists of vowels ('a', 'e', 'i', 'o', and 'u') and has all five vowels present in it.
Given a string word, return the number of vowel substrings in word.
Example 1:
Input: word = “aeiouu”
Output: 2
Explanation: The vowel substrings of word are as follows (underlined):
-
“aeiouu”
-
“aeiouu”
Example 2:
Input: word = “unicornarihan”
Output: 0
Explanation: Not all 5 vowels are present, so there are no vowel substrings.
Example 3:
Input: word = “cuaieuouac”
Output: 7
Explanation: The vowel substrings of word are as follows (underlined):
-
“cuaieuouac”
-
“cuaieuouac”
-
“cuaieuouac”
-
“cuaieuouac”
-
“cuaieuouac”
-
“cuaieuouac”
-
“cuaieuouac”
Constraints:
1 <= word.length <= 100wordconsists of lowercase English letters only.
Solution
class Solution {
fun countVowelSubstrings(word: String): Int {
var count = 0
val vowels: Set<Char> = HashSet(listOf('a', 'e', 'i', 'o', 'u'))
val window: MutableSet<Char> = HashSet()
for (i in word.indices) {
window.clear()
if (vowels.contains(word[i])) {
window.add(word[i])
for (j in i + 1 until word.length) {
if (!vowels.contains(word[j])) {
break
} else {
window.add(word[j])
if (window.size == 5) {
count++
}
}
}
}
}
return count
}
}