7a

.gitignore

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 tags
 22
 TAGS
+*.jar

Makefile

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+all:
+	kotlinc -include-runtime -d k7.jar seven.kt

run

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+#!/usr/bin/env bash
+exec java -jar k7.jar

seven.kt

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+/**
+ * absolute ranking (as opposed to hands ranked against another set of hands)
+ * only care about the partitioning, not the pips
+ */
+fun hand_absrank(h: List<Pair<Int, Int>>): Int = h
+    .fold("") { acc, (_, r) -> acc + r.toString() }
+    .let {
+        mapOf("5" to 6, "41" to 5, "32" to 4, // https://oeis.org/A322761
+        "311" to 3, "221" to 2, "2111" to 1, "11111" to 0)[it]!!
+    }
+
+/**
+ * In:  [10, 5, ...
+ * Out: [(5, 3), ...
+ */
+fun card_count(hand: List<Int>): List<Pair<Int, Int>> = hand
+    .groupingBy { it }.eachCount()
+    .toList().sortedByDescending { it.second }
+
+/**
+ * In:  [10, 5, ...
+ * Out: 10*16^4 + 5*16^3 + 5*16^2 + 11*16 + 5 + 3*16^5 = 3823029
+ */
+fun score(h: List<Int>): Int {
+    return hand_absrank(card_count(h)) * 1048576 +
+        h.foldRight(Pair(1, 0)) { it, (mul, acc) -> Pair(mul * 16, acc + it * mul) }.second
+}
+
+/**
+ * In:  T55J5
+ * Out: [10, 5, ...]
+ */
+fun cards(hand: String): List<Int> = hand.toCharArray() // T55J5
+    .map { mapOf<Char, Int>('T' to 10, 'J' to 11, 'Q' to 12, 'K' to 13, 'A' to 14)[it] ?:
+        (it - '0').toInt() }
+
+fun main() {
+    val hands = generateSequence(::readLine).map { it // "T55J5 684"
+        .split(' ') // "T55J5" "684"
+        .let { Pair<List<Int>, Int>(cards(it[0]), it[1].toInt()) }
+    } // [10, 5, ...], 684
+    val scored = hands.map { (hand, bid) -> listOf(hand, bid, score(hand)) }
+    val sorted = scored.toList().sortedBy { it[2] as Int }
+    //sorted.forEach { println(it) }
+    val ranked = sorted.mapIndexed { i, l ->
+        Pair(i + 1, l[1]) }
+    val sum = ranked.fold(0) { acc, (rank, bid) -> acc + rank * bid as Int}
+    println(sum)
+}

test7

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+32T3K 765
+T55J5 684
+KK677 28
+KTJJT 220
+QQQJA 483