[백준 - 2636] 치즈

문제링크

import java.util.*

fun main() {
    val bufferedReader = System.`in`.bufferedReader()
    val bufferedWriter = System.out.bufferedWriter()

    val (height, width) = bufferedReader.readLine().split(" ").map { it.toInt() }
    val rectangle = mutableListOf<MutableList<Int>>()
    for (i in 0 until height) {
        val row = bufferedReader.readLine().split(" ").map { it.toInt() }.toMutableList()
        rectangle.add(row)
    }

    var hour = 0
    var numberOfRemainedCheese = 0
    while (true) {
        val numberOfCheese = getNumberOfCheese(height, width, rectangle)
        val numberOfRemovedCheeseBoundary = getNumberOfRemovedCheeseBoundary(height, width, rectangle)
        hour++
        if (numberOfCheese == numberOfRemovedCheeseBoundary) {
            numberOfRemainedCheese = numberOfCheese
            break
        }
    }
    bufferedWriter.write("$hour\n$numberOfRemainedCheese")

    bufferedReader.close()
    bufferedWriter.close()
}

fun getNumberOfCheese(height: Int, width: Int, rectangle: MutableList<MutableList<Int>>): Int {
    var numberOfCheese = 0
    for (i in 0 until height) {
        for (j in 0 until width) {
            if (rectangle[i][j] == 1) numberOfCheese++
        }
    }
    return numberOfCheese
}

fun getNumberOfRemovedCheeseBoundary(height: Int, width: Int, rectangle: MutableList<MutableList<Int>>): Int {
    var numberOfRemovedCheeseBoundary = 0
    val dy = listOf(0, 1, 0, -1)
    val dx = listOf(1, 0, -1, 0)
    val visited = Array(height) { Array(width) { false } }
    val queue: Queue<Pair<Int, Int>> = LinkedList()
    queue.add(Pair(0, 0))
    visited[0][0] = true

    while (queue.isNotEmpty()) {
        val (y, x) = queue.poll()

        for (i in 0..3) {
            val ny = y + dy[i]
            val nx = x + dx[i]
            if (ny in 0 until height && nx in 0 until width && !visited[ny][nx]) {
                if (rectangle[ny][nx] == 0) {
                    queue.add(Pair(ny, nx))
                    visited[ny][nx] = true
                } else {
                    rectangle[ny][nx] = 0 // ◀ remove cheese boundary
                    visited[ny][nx] = true
                    numberOfRemovedCheeseBoundary++
                }
            }
        }
    }
    return numberOfRemovedCheeseBoundary
}

주석 없는 코드를 만들기 위해 노력하는 개발자입니다.

혹시라도 의도가 분명하지 않아보이는 (이해가 되지 않는) 코드가 있으시다면 편하게 답변 달아주시면 정말 감사하겠습니다.