LeetCode in Kotlin
1704. Determine if String Halves Are Alike
Easy
You are given a string s of even length. Split this string into two halves of equal lengths, and let a be the first half and b be the second half.
Two strings are alike if they have the same number of vowels ('a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U'). Notice that s contains uppercase and lowercase letters.
Return true if a and b are alike. Otherwise, return false.
Example 1:
Input: s = “book”
Output: true
Explanation: a = “bo” and b = “ok”. a has 1 vowel and b has 1 vowel. Therefore, they are alike.
Example 2:
Input: s = “textbook”
Output: false
Explanation: a = “text” and b = “book”. a has 1 vowel whereas b has 2. Therefore, they are not alike. Notice that the vowel o is counted twice.
Constraints:
2 <= s.length <= 1000s.lengthis even.sconsists of uppercase and lowercase letters.
Solution
class Solution {
fun halvesAreAlike(s: String): Boolean {
return if (s.isEmpty()) {
false
} else countVowel(0, s.length / 2, s) == countVowel(s.length / 2, s.length, s)
}
private fun countVowel(start: Int, end: Int, s: String): Int {
var c = 0
for (i in start until end) {
val ch = s[i]
if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' ||
ch == 'u' || ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U'
) {
c++
}
}
return c
}
}