[전현수] - 괄호 회전하기, 후위 표기식, 캐슬 디펜스

src/main/kotlin/hyunsoo/65week/괄호 회전하기.kt

@@ -0,0 +1,69 @@
+package hyunsoo.`65week`
+
+import java.util.*
+ /**
+ *
+ * <문제>
+ * [괄호 회전하기](https://school.programmers.co.kr/learn/courses/30/lessons/76502)
+ *
+ * - 아이디어
+ *
+ * - 트러블 슈팅
+ *
+ */
+class `전현수_괄호_희전하기` {
+
+    private val opens = listOf('(', '[', '{')
+
+    fun solution(s: String): Int {
+        var answer = 0
+
+        val target = s + s
+
+        var start = 0
+        repeat(s.length) {
+            if (target.slice(start until start + s.length).isAlright()) answer++
+            start++
+        }
+
+        return answer
+    }
+
+     private fun String.isAlright(): Boolean {
+
+         val stack = Stack<Char>()
+
+         this.forEachIndexed { index, ch ->
+
+             if (ch in opens) {
+                 stack.add(ch)
+             }
+             else {
+
+                 if (stack.isEmpty()) return false
+
+                 when (stack.peek()) {
+                     '(' -> {
+                         if (ch == ')') stack.pop()
+                         else return false
+                     }
+                     '[' -> {
+                         if (ch == ']') stack.pop()
+                         else return false
+                     }
+                     '{' -> {
+                         if (ch == '}') stack.pop()
+                         else return false
+                     }
+                 }
+             }
+         }
+
+         return stack.isEmpty()
+
+     }
+}
+
+fun main() {
+    전현수_괄호_희전하기().solution("[](){}")
+}

src/main/kotlin/hyunsoo/65week/캐슬 디펜스.kt

@@ -0,0 +1,132 @@
+package hyunsoo.`65week`
+
+import java.util.LinkedList
+import java.util.Queue
+
+/**
+ *
+ * <문제>
+ * [캐슬 디펜스](https://www.acmicpc.net/problem/17135)
+ *
+ * - 아이디어
+ *
+ * - 트러블 슈팅
+ *
+ */
+class `전현수_캐슬_디펜스` {
+
+    private data class Position(val x: Int, val y: Int)
+
+    private data class Bundle(val pos: Position, val range: Int)
+
+    private var n = 0
+    private var m = 0
+    private var range = 0
+
+    private val board = mutableListOf<MutableList<Int>>()
+
+    private val pickedNumList = mutableListOf<Int>()
+
+    var answer = 0
+
+    // 좌 상 우
+    private val dirs = listOf(
+        Position(0, -1),
+        Position(-1, 0),
+        Position(0, 1),
+    )
+
+    fun solution() {
+
+        readln().split(" ").map { it.toInt() }.apply {
+            n = this[0]
+            m = this[1]
+            range = this[2]
+        }
+
+        repeat(n) { rowIndex ->
+            val row = readln().split(" ").map { it.toInt() } as MutableList
+            board.add(row)
+        }
+
+        for (i in 0..m - 3) {
+            getCombinations(3, 0, i)
+        }
+
+        println(answer)
+    }
+
+    private fun getCombinations(depth: Int, cnt: Int, startIndex: Int) {
+
+        if (depth == cnt) {
+            check(pickedNumList)
+        }
+
+        for (index in startIndex until m) {
+            pickedNumList.add(index)
+            getCombinations(depth, cnt + 1, index + 1)
+            pickedNumList.removeLast()
+        }
+
+    }
+
+    private fun check(archersYList: List<Int>) {
+
+        val curBoard = board.deepCopy()
+
+        var curEliminatedCnt = 0
+
+        for (archerX in n - 1 downTo 0) {
+
+            val targetSet = mutableSetOf<Position>()
+
+            archersYList.forEach { curArcherY ->
+
+                val queue: Queue<Bundle> = LinkedList()
+
+                queue.add(Bundle(Position(archerX, curArcherY), 1))
+
+                while (queue.isNotEmpty()) {
+
+                    val (curPos, curRange) = queue.poll()
+
+                    if (curBoard[curPos.x][curPos.y] == 1) {
+                        targetSet.add(Position(curPos.x, curPos.y))
+                        return@forEach
+                    }
+
+                    if (curRange < range) {
+                        dirs.forEach dir@{
+                            val nx = curPos.x + it.x
+                            val ny = curPos.y + it.y
+
+
+                            if (nx !in 0 until n ||
+                                ny !in 0 until m
+                            ) return@dir
+
+                            queue.add(Bundle(Position(nx, ny), curRange + 1))
+                        }
+                    }
+                }
+            }
+
+            targetSet.forEach {
+                curBoard[it.x][it.y] = 0
+                curEliminatedCnt++
+            }
+        }
+
+        if (answer < curEliminatedCnt) answer = curEliminatedCnt
+
+    }
+
+    private fun MutableList<MutableList<Int>>.deepCopy() =
+        this.map {
+            it.toMutableList()
+        }.toMutableList()
+}
+
+fun main() {
+    전현수_캐슬_디펜스().solution()
+}

src/main/kotlin/hyunsoo/65week/후위 표기식.kt

@@ -0,0 +1,66 @@
+package hyunsoo.`65week`
+
+import java.util.*
+
+/**
+ *
+ * <문제>
+ * [후위 표기식](https://www.acmicpc.net/problem/1918)
+ *
+ * - 아이디어
+ *
+ * - 트러블 슈팅
+ *
+ */
+class `전현수_후위_표기식` {
+
+    fun solution() {
+
+        val s = readln()
+        val sb = StringBuilder()
+        val stack = Stack<Char>()
+
+        s.forEach { ch ->
+            when (ch) {
+                '(' -> {
+                    stack.push('(')
+                }
+
+                '*', '/' -> {
+                    while (stack.isNotEmpty()) {
+                        if (stack.peek() == '*' || stack.peek() == '/') sb.append(stack.pop())
+                        else break
+                    }
+                    stack.push(ch)
+                }
+
+                '+', '-' -> {
+                    while (stack.isNotEmpty()) {
+                        if (stack.peek() == '(') break
+                        sb.append(stack.pop())
+                    }
+                    stack.push(ch)
+                }
+
+                ')' -> {
+                    while (stack.isNotEmpty()) {
+                        val fromStack = stack.pop()
+                        if (fromStack == '(') break
+                        sb.append(fromStack)
+                    }
+                }
+
+                else -> {
+                    sb.append(ch)
+                }
+            }
+        }
+
+        while (stack.isNotEmpty()) sb.append(stack.pop())
+        println(sb)
+    }
+}
+
+fun main() {
+    전현수_후위_표기식().solution()
+}