LeetCode in Kotlin
424. Longest Repeating Character Replacement
Medium
You are given a string s and an integer k. You can choose any character of the string and change it to any other uppercase English character. You can perform this operation at most k times.
Return the length of the longest substring containing the same letter you can get after performing the above operations.
Example 1:
Input: s = “ABAB”, k = 2
Output: 4
Explanation: Replace the two ‘A’s with two ‘B’s or vice versa.
Example 2:
Input: s = “AABABBA”, k = 1
Output: 4
Explanation: Replace the one ‘A’ in the middle with ‘B’ and form “AABBBBA”. The substring “BBBB” has the longest repeating letters, which is 4.
Constraints:
1 <= s.length <= 105sconsists of only uppercase English letters.0 <= k <= s.length
Solution
class Solution {
fun characterReplacement(s: String, k: Int): Int {
var left = 0
var right = 0
val len = s.length
val count = IntArray(256)
val sArr = s.toCharArray()
var currMax = 0
var maxLen = 0
var curr: Char
while (right < len) {
curr = sArr[right]
count[curr.code]++
currMax = Math.max(currMax, count[curr.code])
if (right - left + 1 <= currMax + k) {
maxLen = Math.max(maxLen, right - left + 1)
}
while (right - left + 1 > currMax + k) {
curr = sArr[left]
count[curr.code]--
left++
}
right++
}
return maxLen
}
}