83-tgyuuAn

tgyuuAn/README.md

@@ -86,4 +86,5 @@
 | 80차시 | 2024.11.11 |  다익스트라  | <a href="https://www.acmicpc.net/problem/11779">최소비용 구하기 2</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/254
 | 81차시 | 2024.11.15 |  이분 탐색  | <a href="https://www.acmicpc.net/problem/1701">Cubeeditor</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/255
 | 82차시 | 2024.11.22 |  희소 배열  | <a href="https://www.acmicpc.net/problem/17435">합성함수와 쿼리</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/257
+| 83차시 | 2024.12.01 |  수학 + 구현 | <a href="https://www.acmicpc.net/problem/1033">칵테일</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/259
 ---

tgyuuAn/수학/칵테일.kt

@@ -0,0 +1,98 @@
+fun gcd(a: Int, b: Int): Int {
+    var tempA = maxOf(a, b)
+    var tempB = minOf(a, b)
+
+    if(tempB <= 0){
+        return 0
+    }
+
+    while (tempA % tempB >= 1){
+        val tempC = tempA%tempB
+        tempA = tempB
+        tempB = tempC
+    }
+
+    return tempB
+}
+
+fun main() {
+    val N = readln().toInt()
+    val ratio = IntArray(N){ 1 }
+    val linked = Array(N) { mutableListOf<Int>() }
+
+    repeat(N-1){
+        val info = readln().split(" ").map{ it.toInt() }
+        val a = info[0]
+        val b = info[1]
+        var p = info[2]
+        var q = info[3]
+        val divGcd = gcd(p, q)
+        p /= divGcd
+        q /= divGcd
+
+        // println("$a $b $p $q")
+
+        val aLinked = mutableSetOf<Int>(a)
+        val aDeq = ArrayDeque<Int>()
+        aDeq.addFirst(a)
+        while(!aDeq.isEmpty()){
+            val now = aDeq.removeFirst()
+
+            for(neighbor in linked[now]){
+                if(neighbor in aLinked){
+                    continue
+                }
+
+                aLinked.add(neighbor)
+                aDeq.addLast(neighbor)
+            }
+        }
+
+        val bLinked = mutableSetOf<Int>(b)
+        val bDeq = ArrayDeque<Int>()
+        bDeq.addFirst(b)
+        while(!bDeq.isEmpty()){
+            val now = bDeq.removeFirst()
+
+            for(neighbor in linked[now]){
+                if(neighbor in bLinked){
+                    continue
+                }
+
+                bLinked.add(neighbor)
+                bDeq.addLast(neighbor)
+            }
+        }
+
+        // println("$aLinked $bLinked")
+
+        val tempARatio = ratio[a]
+        val tempBRatio = ratio[b]
+
+        for(aNeighbor in aLinked){
+            ratio[aNeighbor] *= (tempBRatio * p)
+        }
+
+        for(bNeighbor in bLinked){
+            ratio[bNeighbor] *= (tempARatio * q)
+        }
+
+        linked[a].add(b)
+        linked[b].add(a)
+
+        // println(linked.toList().toString())
+        // println(ratio.toList().toString())
+        // println()
+    }
+
+    val allGcd = ratio.reduce(::gcd)
+    for(elemIdx in 0 until ratio.size){
+        ratio[elemIdx] /= allGcd
+    }
+
+    println(ratio.toList()
+    .toString()
+    .replace(",", "")
+    .replace("[", "")
+    .replace("]", ""))
+}