diff --git "a/src/4week/acw/\352\267\274\354\206\220\354\213\244.kt" "b/src/4week/acw/\352\267\274\354\206\220\354\213\244.kt"
new file mode 100644
index 0000000..d77659b
--- /dev/null
+++ "b/src/4week/acw/\352\267\274\354\206\220\354\213\244.kt"
@@ -0,0 +1,50 @@
+package `4week`.acw
+
+class `acw근손실` {
+ lateinit var exerciseKits: List<Int>
+ lateinit var visit: Array<Boolean>
+ var cnt = 0
+
+
+ fun makePermutation(arr: MutableList<Int>, power: Int, day: Int, N: Int, K: Int) {
+ //순열구성하기
+ val powerNow = power + (arr.takeIf { it.isNotEmpty() }?.let { it.last() - K } ?: 0)
+
+ if (powerNow < 500) {
+ return
+ }
+
+ if (day == N) {
+ cnt++
+ return
+ }
+
+ for (i in 0 until N) {
+ if (visit[i]) {
+ continue
+ }
+
+ arr.add(exerciseKits[i])
+ visit[i] = true
+ makePermutation(arr, powerNow, day + 1, N, K)
+ arr.remove(exerciseKits[i])
+ visit[i] = false
+ }
+ }
+
+
+ fun solution() {
+ val (N, K) = readln().split(" ").map { it.toInt() }
+ exerciseKits = readln().split(" ").map { it.toInt() }
+ visit = Array(N) { false }
+ makePermutation(mutableListOf(), 500, 0, N, K)
+
+ println(cnt)
+
+ }
+}
+
+fun main() {
+ val sol = `acw근손실`()
+ sol.solution()
+}
\ No newline at end of file
diff --git "a/src/4week/acw/\354\243\274\354\260\250\354\232\224\352\270\210\352\263\204\354\202\260.kt" "b/src/4week/acw/\354\243\274\354\260\250\354\232\224\352\270\210\352\263\204\354\202\260.kt"
new file mode 100644
index 0000000..03bde37
--- /dev/null
+++ "b/src/4week/acw/\354\243\274\354\260\250\354\232\224\352\270\210\352\263\204\354\202\260.kt"
@@ -0,0 +1,85 @@
+import java.util.LinkedList
+
+class Solution {
+
+ val recordsArr = Array(10000) { LinkedList<String>() }
+ val feeArr = Array(10000) { 0 }
+
+ data class Time(var hour: Int, var min: Int) {
+
+ constructor(hourAndMin: List<Int>) : this(hourAndMin[0], hourAndMin[1]) {
+ this.hour = hourAndMin[0]
+ this.min = hourAndMin[1]
+ }
+
+ companion object {
+ fun calcUsingTime(inTime: Time, outTime: Time): Int {
+ return (outTime.hour * 60 + outTime.min - inTime.hour * 60 - inTime.min)
+ }
+ }
+ }
+
+ fun String.timeSplit() = split(":").map { it.toInt() }
+
+ fun solution(fees: IntArray, records: Array<String>): IntArray {
+ var answer: IntArray = intArrayOf()
+
+ for (i in records) {
+ val (time, num, inout) = i.split(" ")
+ if (inout == "IN") {
+ recordsArr[num.toInt()].add(time)
+ } else {
+ //out이 나올경우에는 바로 해당번호에 대해 처리를 해준다.
+ val inTime = Time((recordsArr[num.toInt()].removeLast().timeSplit()))
+ val outTime = Time(time.timeSplit())
+
+ val usingTime = Time.calcUsingTime(inTime, outTime)
+ feeArr[num.toInt()] += usingTime
+ }
+ }
+
+ for (i in 0 until 10000) {
+ while (recordsArr[i].isNotEmpty()) {
+ val now = Time(recordsArr[i].removeFirst().timeSplit())
+ val usingTime = Time.calcUsingTime(Time(23, 59), now)
+ feeArr[i] += usingTime
+ }
+ }//In은 했는데 Out은 안한경우 위에서 처리가 안되므로 처음부터 돌면서 23:59에서 빼준다.
+
+
+ //요금 계산하기
+ val arr = mutableListOf<Int>()
+ for (i in 0 until 10000) {
+
+ if (feeArr[i] == 0) {
+ continue
+ } else {
+
+ if (feeArr[i] <= fees[0]) {
+ arr.add(fees[1])
+ //기본요금 부과
+ } else {
+ val ceilCheck = (feeArr[i] - fees[0]) % fees[2] != 0//
+ //올림하라했으므로 올림해야하는지 check해주기
+
+ var remain = if (ceilCheck) {
+ (feeArr[i] - fees[0]) / fees[2] + 1
+ } else {
+ (feeArr[i] - fees[0]) / fees[2]
+ }
+
+
+ arr.add(fees[1] + remain * fees[3])
+
+ }
+ }
+
+ }
+ answer = arr.toIntArray()
+
+
+ return answer
+ }
+
+
+}
\ No newline at end of file
diff --git "a/src/4week/acw/\354\247\200\353\246\204\352\270\270.kt" "b/src/4week/acw/\354\247\200\353\246\204\352\270\270.kt"
new file mode 100644
index 0000000..a84e21f
--- /dev/null
+++ "b/src/4week/acw/\354\247\200\353\246\204\352\270\270.kt"
@@ -0,0 +1,58 @@
+package `4week`.acw
+
+
+import java.util.*
+
+class `acw지름길` {
+ lateinit var distance: Array<Int>
+ var roads = PriorityQueue(Comparator<Triple<Int, Int, Int>> { a, b ->
+ a.first - b.first
+ })
+
+
+ fun solution() {
+ val (K, D) = readln().split(" ").map { it.toInt() }
+ distance = Array(10001) { it }
+
+
+ for (i in 1..K) {
+ val (s, e, c) = readln().split(" ").map { it.toInt() }
+
+ if (e > D) {
+ continue
+ }
+ //목표보다 높은 지점을 향하는 지름길은 받지 않기
+
+ if (c >= (e - s)) {
+ continue
+ }
+ //지름길이 cost가 더 클경우도 받지 않기
+
+ roads.add(Triple(s, e, c))
+ }
+
+ while (roads.isNotEmpty()) {
+ val (s, e, c) = roads.poll()
+ if (distance[e] - distance[s] > c) {
+ distance[e] = distance[s] + c
+ for (j in e + 1..D) {
+ if (distance[j - 1] + 1 < distance[j]) {
+ distance[j] = distance[j - 1] + 1
+ }
+ }
+ // 지름길을 순회하며 더 최소값일 경우 그 뒤의 node들에 대해서 값 갱신
+ }
+ }
+
+
+
+ println(distance[D])
+
+
+ }
+}
+
+fun main() {
+ val sol = `acw지름길`()
+ sol.solution()
+}
diff --git "a/src/4week/acw/\355\206\261\353\213\210\353\260\224\355\200\264.kt" "b/src/4week/acw/\355\206\261\353\213\210\353\260\224\355\200\264.kt"
new file mode 100644
index 0000000..10cd201
--- /dev/null
+++ "b/src/4week/acw/\355\206\261\353\213\210\353\260\224\355\200\264.kt"
@@ -0,0 +1,120 @@
+package `4week`.acw
+
+
+import kotlin.math.pow
+
+//시계방향은 오른쪽shift 반시계는 왼쪽 shift
+const val RIGHT = 5
+const val LEFT = 1
+
+class `acw톱니바퀴` {
+
+ var wheel = Array(4) { 0 }
+ var visit = Array(4) { false }
+ var turn = arrayListOf<Pair<Int, Int>>()
+
+
+ private fun addTurn(w: Int, turnD: Int) {
+ //dfs로 들어가면서 회전해야할 것들 turn에 추가해주기
+
+
+ val wheelNowRight = if (wheel[w] and (1 shl RIGHT) != 0) 1 else 0
+ val wheelNowLeft = if (wheel[w] and (1 shl LEFT) != 0) 1 else 0
+
+ if (w - 1 >= 0) {
+ val leftWheelsRight = if (wheel[w - 1] and (1 shl RIGHT) != 0) 1 else 0
+ if (wheelNowLeft != leftWheelsRight && !visit[w - 1]) {
+ visit[w - 1] = true
+ turn.add(Pair(w - 1, turnD * -1))
+ addTurn(w - 1, turnD * -1)
+ }
+ }
+
+ if (w + 1 < 4) {
+ val rightWheelsLeft = if (wheel[w + 1] and (1 shl LEFT) != 0) 1 else 0
+ if (wheelNowRight != rightWheelsLeft && !visit[w + 1]) {
+ visit[w + 1] = true
+ turn.add(Pair(w + 1, turnD * -1))
+ addTurn(w + 1, turnD * -1)
+ }
+ }
+
+
+ }
+
+ private fun turnWheel() {
+
+ while (turn.isNotEmpty()) {
+ val (w, d) = turn.removeFirst()
+
+ if (d == -1) {
+ //반시계
+ val last = wheel[w] and (1 shl 7)
+
+ wheel[w] = (wheel[w] shl 1) and 255
+ if (last != 0) {
+ wheel[w]++
+ }
+
+ } else {
+ //시계
+ val first = wheel[w] and 1
+
+ wheel[w] = wheel[w] shr 1
+
+ if (first != 0) {
+ wheel[w] += 1 shl 7
+ }
+ }
+
+
+ }
+
+ }
+
+
+ fun solution() {
+ repeat(4) {
+ var input = readln()
+ var m = 128
+ var num = 0
+ for (i in input) {
+ num += (i.digitToInt() * m)
+ m /= 2
+ }//숫자로 바꿔서 저장
+ wheel[it] = num
+
+ }
+
+ val turnCnt = readln().toInt()
+ repeat(turnCnt) {
+ val (w, d) = readln().split(" ").map { it.toInt() }
+ turn.add(Pair(w - 1, d))
+ visit[w - 1] = true
+
+
+ addTurn(w - 1, d)//회전해야할 것들 turn List에 추가해주기
+ turnWheel()// turn List에서 빼서 회전시켜주기
+ visit = Array(4) { false } // visit은 다시 사용해야함으로 다시 false로 초기화
+ }
+
+
+ val answer = wheel.withIndex().sumOf { (idx, value) ->
+ if (value and (1 shl 7) != 0) {
+ (2.0).pow(idx).toInt()
+ } else {
+ 0
+ }
+ }
+
+
+ println(answer)
+
+
+ }
+}
+
+fun main() {
+ val sol = `acw톱니바퀴`()
+ sol.solution()
+}
diff --git "a/src/4week/acw/\355\212\270\353\246\254\354\235\230\353\266\200\353\252\250\354\260\276\352\270\260.kt" "b/src/4week/acw/\355\212\270\353\246\254\354\235\230\353\266\200\353\252\250\354\260\276\352\270\260.kt"
new file mode 100644
index 0000000..11461ae
--- /dev/null
+++ "b/src/4week/acw/\355\212\270\353\246\254\354\235\230\353\266\200\353\252\250\354\260\276\352\270\260.kt"
@@ -0,0 +1,40 @@
+package `4week`.acw
+
+class `acw트리의부모찾기` {
+ lateinit var treeMap: Array<MutableSet<Int>>
+ lateinit var parent: Array<Int>
+ var N = 0
+
+ fun dfs(p: Int) {
+ //p로 전달받은 노드는 부모란 뜻이니까 연결된 노드들은 자식으로 처리해주기
+ //dfs로 이어가면서 같은 처리 해주기
+ for (child in treeMap[p]) {
+ parent[child] = p
+ treeMap[child].remove(p)
+ dfs(child)
+ }
+ }
+
+
+ fun solution() {
+ N = readln().toInt()
+ treeMap = Array(N + 1) { mutableSetOf() }
+ parent = Array(N + 1) { 0 }
+
+ for (i in 1 until N) {
+ val (a, b) = readln().split(" ").map { it.toInt() }
+ treeMap[a].add(b)
+ treeMap[b].add(a)
+ //일단 입력받을 경우 두 node에 대해 상호 연결하기
+ }
+
+ dfs(1)
+ println(parent.drop(2).joinToString("\n"))
+
+ }
+}
+
+fun main() {
+ val sol = `acw트리의부모찾기`()
+ sol.solution()
+}
diff --git "a/src/4week/acw/\355\232\214\354\235\230\354\213\244\353\260\260\354\240\225.kt" "b/src/4week/acw/\355\232\214\354\235\230\354\213\244\353\260\260\354\240\225.kt"
new file mode 100644
index 0000000..3455c5d
--- /dev/null
+++ "b/src/4week/acw/\355\232\214\354\235\230\354\213\244\353\260\260\354\240\225.kt"
@@ -0,0 +1,46 @@
+package `4week`.acw
+
+import java.util.PriorityQueue
+
+
+class `acw회의실배정` {
+ val conferance = PriorityQueue(
+ compareBy<Pair<Int, Int>> {it.second}.thenBy { it.first }
+ )
+// 종료시간이 빠른것을 기준으로 정렬한다.
+// 종료시간이 같을 경우 시작시간이 더 빠른것을 위주로 정렬해야한다. -> 시작시간과 종료시간이 같은 회의가 있을 수 있기 때문
+// ex) 5,6 / 6,6 이 있는데 6,6이 먼저 뽑힐 경우 56 /66이 모두 사용될 수 있음에도 불구하고 56은 선택되지 못한다.
+
+ fun solution() {
+ val N = readln().toInt()
+ var answer = 1
+ var lastConferance = Pair(0, 0)
+
+ repeat(N) {
+ val (s, e) = readln().split(" ").map { it.toInt() }
+ conferance.add(Pair(s, e))
+
+ }
+ lastConferance = conferance.poll()
+
+
+ while (conferance.isNotEmpty()) {
+ val nowConferance = conferance.poll()
+ if (nowConferance.first >= lastConferance.second) {
+ lastConferance = nowConferance
+ answer++
+ }
+
+ }
+ println(answer)
+
+
+ }
+
+}
+
+fun main() {
+ val sol = `acw회의실배정`()
+ sol.solution()
+}
+