Solve go/blackjack

go/blackjack/blackjack.go

@@ -2,11 +2,63 @@ package blackjack
 
 // ParseCard returns the integer value of a card following blackjack ruleset.
 func ParseCard(card string) int {
-	panic("Please implement the ParseCard function")
+	switch card {
+	case "ace":
+		return 11
+	case "king", "queen", "jack", "ten":
+		return 10
+	case "nine":
+		return 9
+	case "eight":
+		return 8
+	case "seven":
+		return 7
+	case "six":
+		return 6
+	case "five":
+		return 5
+	case "four":
+		return 4
+	case "three":
+		return 3
+	case "two":
+		return 2
+	default:
+		return 0
+	}
 }
 
 // FirstTurn returns the decision for the first turn, given two cards of the
 // player and one card of the dealer.
 func FirstTurn(card1, card2, dealerCard string) string {
-	panic("Please implement the FirstTurn function")
+	playerCardSum := ParseCard(card1) + ParseCard(card2)
+	dealerCardValue := ParseCard(dealerCard)
+
+	const (
+		stand = "S"
+		hit   = "H"
+		split = "P"
+		win   = "W"
+	)
+
+	switch playerCardSum {
+	case 22:
+		return split
+	case 21:
+		if dealerCardValue < 10 {
+			return win
+		} else {
+			return stand
+		}
+	case 17, 18, 19, 20:
+		return stand
+	case 12, 13, 14, 15, 16:
+		if dealerCardValue >= 7 {
+			return hit
+		} else {
+			return stand
+		}
+	default:
+		return hit
+	}
 }