LeetCode in Kotlin
3557. Find Maximum Number of Non Intersecting Substrings
Medium
You are given a string word.
Return the maximum number of non-intersecting **substring** of word that are at least four characters long and start and end with the same letter.
Example 1:
Input: word = “abcdeafdef”
Output: 2
Explanation:
The two substrings are "abcdea" and "fdef".
Example 2:
Input: word = “bcdaaaab”
Output: 1
Explanation:
The only substring is "aaaa". Note that we cannot also choose "bcdaaaab" since it intersects with the other substring.
Constraints:
1 <= word.length <= 2 * 105wordconsists only of lowercase English letters.
Solution
class Solution {
fun maxSubstrings(s: String): Int {
val prev = IntArray(26)
var r = 0
prev.fill(-1)
for (i in 0..<s.length) {
val j = s[i].code - 'a'.code
if (prev[j] != -1 && i - prev[j] + 1 >= 4) {
++r
prev.fill(-1)
} else if (prev[j] == -1) {
prev[j] = i
}
}
return r
}
}