78 lines
1.8 KiB
Kotlin
78 lines
1.8 KiB
Kotlin
import java.util.Scanner
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enum class Direction {
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NORTH {
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override fun moveFrom(row: Int, col: Int): Pair<Int, Int> {
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return Pair(row-1, col)
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}
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}, SOUTH {
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override fun moveFrom(row: Int, col: Int): Pair<Int, Int> {
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return Pair(row+1, col)
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}
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}, WEST {
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override fun moveFrom(row: Int, col: Int): Pair<Int, Int> {
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return Pair(row, col-1)
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}
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}, EAST {
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override fun moveFrom(row: Int, col: Int): Pair<Int, Int> {
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return Pair(row, col+1)
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}
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};
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fun turnRight(): Direction {
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return when (this) {
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NORTH -> EAST
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EAST -> SOUTH
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SOUTH -> WEST
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WEST -> NORTH
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}
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}
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abstract fun moveFrom(row: Int, col: Int): Pair<Int, Int>
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}
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val scanner = Scanner(System.`in`)
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val map = ArrayList<Array<Char>>()
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var rows = 0
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var guardRow = -1
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var guardCol = -1
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while (scanner.hasNextLine()) {
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val line = scanner.nextLine()
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val pos = line.indexOf('^')
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if (pos != -1) {
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guardRow = rows
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guardCol = pos
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}
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val chars = line.toCharArray().toTypedArray()
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map.add(chars)
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rows++
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}
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var facing = Direction.NORTH
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var visitedCount = 0
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walk@ while (true) {
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if (map[guardRow][guardCol] != 'X') {
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visitedCount++
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}
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map[guardRow][guardCol] = 'X'
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var seeking = true
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do {
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val (nextRow, nextCol) = facing.moveFrom(guardRow, guardCol)
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if (nextRow < 0 || nextRow >= map.size || nextCol < 0 || nextCol >= map[nextCol].size) {
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break@walk
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}
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if (map[nextRow][nextCol] == '#') {
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facing = facing.turnRight()
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} else {
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guardRow = nextRow
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guardCol = nextCol
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seeking = false
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}
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} while (seeking)
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}
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println(visitedCount)
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