complete day 7

day07.go

@@ -149,6 +149,123 @@ func camelrank(hand hand) (rank, []int) {
 	return highCard, hand.values
 }
 
+func camelrankjoker(hand hand) (rank, []int, int) {
+	counts := make([]int, 14)
+	jokers := 0
+	hand.values = make([]int, len(hand.cards))
+
+	for i, r := range hand.cards {
+		switch r {
+		case '1':
+			counts[0] = counts[0] + 1
+			hand.values[i] = 1
+		case '2':
+			counts[1] = counts[1] + 1
+			hand.values[i] = 2
+		case '3':
+			counts[2] = counts[2] + 1
+			hand.values[i] = 3
+		case '4':
+			counts[3] = counts[3] + 1
+			hand.values[i] = 4
+		case '5':
+			counts[4] = counts[4] + 1
+			hand.values[i] = 5
+		case '6':
+			counts[5] = counts[5] + 1
+			hand.values[i] = 6
+		case '7':
+			counts[6] = counts[6] + 1
+			hand.values[i] = 7
+		case '8':
+			counts[7] = counts[7] + 1
+			hand.values[i] = 8
+		case '9':
+			counts[8] = counts[8] + 1
+			hand.values[i] = 9
+		case 'T':
+			counts[9] = counts[9] + 1
+			hand.values[i] = 10
+		case 'J':
+    		jokers++
+			hand.values[i] = 1
+		case 'Q':
+			counts[11] = counts[11] + 1
+			hand.values[i] = 12
+		case 'K':
+			counts[12] = counts[12] + 1
+			hand.values[i] = 13
+		case 'A':
+			counts[13] = counts[13] + 1
+			hand.values[i] = 14
+		}
+	}
+
+	var (
+		seenPair         bool
+		seenThreeOfAKind bool
+	)
+
+	for _, count := range counts {
+		switch count {
+		case 0:
+		case 1:
+			continue
+		case 2:
+			if seenPair {
+				return twoPair, hand.values, jokers
+			} else if seenThreeOfAKind {
+				return fullHouse, hand.values, jokers
+			}
+			seenPair = true
+		case 3:
+			if seenPair {
+				return fullHouse, hand.values, jokers
+			}
+			seenThreeOfAKind = true
+		case 4:
+			return fourOfAKind, hand.values, jokers
+		case 5:
+			return fiveOfAKind, hand.values, jokers
+		}
+	}
+
+	if seenPair {
+		return onePair, hand.values , jokers
+	} else if seenThreeOfAKind {
+		return threeOfAKind, hand.values, jokers
+	}
+
+	return highCard, hand.values, jokers
+}
+
+func upgraderank(hand hand, jokers int) rank {
+	var upgrades [4]rank
+	switch hand.rank {
+	case highCard:
+		if jokers == 5 {
+			return fiveOfAKind
+		}
+		upgrades = [4]rank{onePair, threeOfAKind, fourOfAKind, fiveOfAKind}
+	case onePair:
+		upgrades = [4]rank{threeOfAKind, fourOfAKind, fiveOfAKind, fiveOfAKind}
+	case twoPair:
+		upgrades = [4]rank{fullHouse, fullHouse, fullHouse, fullHouse}
+	case threeOfAKind:
+		upgrades = [4]rank{fourOfAKind, fiveOfAKind, fiveOfAKind, fiveOfAKind}
+	case fullHouse:
+		upgrades = [4]rank{fullHouse, fullHouse, fullHouse, fullHouse}
+	case fourOfAKind:
+		upgrades = [4]rank{fiveOfAKind, fiveOfAKind, fiveOfAKind, fiveOfAKind}
+	case fiveOfAKind:
+		upgrades = [4]rank{fiveOfAKind, fiveOfAKind, fiveOfAKind, fiveOfAKind}
+	}
+	if jokers > 0 {
+		return upgrades[jokers-1]
+	}
+	return hand.rank
+}
+
 func (d day07) solve1(r io.Reader) string {
 	total := 0
 	var hands hands = make([]hand, 0)
@@ -179,5 +296,32 @@ func (d day07) solve1(r io.Reader) string {
 }
 
 func (d day07) solve2(r io.Reader) string {
-	return "incomplete"
+	total := 0
+	var hands hands = make([]hand, 0)
+	scanner := bufio.NewScanner(r)
+	scanner.Split(bufio.ScanWords)
+
+	for i, w := 0, 0; scanner.Scan(); w++ {
+		word := scanner.Text()
+		if w%2 == 0 {
+			hand := hand{cards: []rune(word)}
+			var jokers int
+			hand.rank, hand.values, jokers = camelrankjoker(hand)
+			hand.rank = upgraderank(hand, jokers)
+			hands = append(hands, hand)
+		} else {
+			val, err := strconv.ParseInt(word, 10, 64)
+			if err != nil {
+				panic(err)
+			}
+			hands[i].bid = int(val)
+			i++
+		}
+	}
+
+	sort.Sort(hands)
+	for i, hand := range hands {
+		total += hand.bid * (i + 1)
+	}
+	return fmt.Sprintf("%d", total)
 }

main_test.go

@@ -189,4 +189,10 @@ QQQJA 483`
 	if ans != res {
 		t.Errorf("solve1() = %s; wanted %s", res, ans)
 	}
+
+	ans = "5905"
+	res = puzzle.solve2(strings.NewReader(input))
+	if ans != res {
+		t.Errorf("solve2() = %s; wanted %s", res, ans)
+	}
 }