[BOJ] 16472번 : 고냥이

코드

import java.lang.*
import java.util.*

var n = 0
var str = ""
var result = 0

val map = HashMap<Char, Int>()

fun main() {
    input()
    func()
    println(result)
}

fun input() {
    val sc = Scanner(System.`in`)

    n = sc.nextInt()
    str = sc.next()

    sc.close()
}

fun func() {
    var left = 0
    var right = 0

    while (true) {
        val length = map.keys.size

        if (length <= n) {
            if (result < (right - left))
                result = right - left

            if (right == str.length) return

            val count = map[str[right]] ?: 0
            map[str[right]] = count + 1

            ++right
        } else {
            val count = map[str[left]]!!

            if (count == 1) map.remove(str[left])
            else map[str[left]] = count - 1

            ++left
        }
    }
}