Solves

work/Kotlin/백준/Gold/no1916/Main.kt

@@ -0,0 +1,95 @@
+package 백준.Gold.no1916
+
+import java.io.BufferedOutputStream
+import java.io.DataInputStream
+import java.util.*
+
+private const val IBS = 50_000
+private const val OBS = 3_000
+private val O = BufferedOutputStream(System.`out`, OBS)
+private val I = DataInputStream(System.`in`)
+private val IB = ByteArray(IBS)
+private var Ii = 0
+private var Il = 0
+private const val EOF = -1
+
+private fun r(): Byte {
+  if (Ii == Il) {
+    Il = I.read(IB, 0, IBS)
+    if (Il == EOF) IB[0] = EOF.toByte()
+    Ii = 0
+  }
+  return IB[Ii++]
+}
+
+private val NUM = 48..57
+private fun i(): Int {
+  var v = 0
+  var s = 1
+  var c: Byte
+  while (r().also { c = it } in NUM || c == 45.toByte()) {
+    when (c) {
+      in NUM -> v = v * 10 + c - 48
+      else -> s = -1
+    }
+  }
+  return s * v
+}
+
+
+private const val WS = 10
+private val WB = ByteArray(WS)
+private fun w(
+  num: Long,
+) {
+  var v = if (num >= 0) num
+  else {
+    O.write(45)
+    -num
+  }
+  var pos = WS - 1
+  do {
+    WB[pos--] = (v % 10 + 48).toByte()
+    v /= 10
+  } while (v > 0)
+  pos++
+  O.write(WB, pos, WS - pos)
+}
+
+private const val INF = Long.MAX_VALUE
+private const val SEP = 10_000
+
+fun main() {
+  val n = i()
+  val m = i()
+
+  val g = Array(n + 1) { mutableMapOf<Int, Long>() }
+  val cost = Array(n + 1) { INF }
+  repeat(m) {
+    val fr = i()
+    val to = i()
+    val c = i().toLong()
+    if ((g[fr][to] ?: INF) > c) g[fr][to] = c
+  }
+
+  val fr = i().toLong()
+  val to = i()
+  val q = PriorityQueue<Long>()
+  q.add(fr)
+  while (q.isNotEmpty()) {
+    val e = q.poll()
+    val acc = e / SEP
+    val f = e % SEP
+    if (cost[to] <= acc) continue
+    for (etr in g[f.toInt()]) {
+      val t = etr.key
+      val c = etr.value
+      val nAcc = acc + c
+      if (cost[t] <= nAcc) continue
+      cost[t] = nAcc
+      q.add(nAcc * SEP + t)
+    }
+  }
+  w(cost[to])
+  O.flush()
+}