Add Yatzy in Python

1 files changed, 255 insertions, 0 deletions

diff --git a/python/yatzy/yatzy.py b/python/yatzy/yatzy.py
new file mode 100644
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+++ b/python/yatzy/yatzy.py
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+import random
+import sys
+import os
+
+
+# Clear the screen
+def clear_screen():
+	if os.name == 'nt':         # Windows
+		os.system('cls')
+	else:                       # Everyone else
+		os.system('clear')
+
+
+# Count the number of unique pairs in DICE
+def number_of_pairs(dice):
+	pairs = 0
+	for i in range(1, 7):
+		pairs += dice.count(i) >= 2
+	return pairs
+
+
+# Check if all the dice are valid
+def dice_are_valid(dice):
+	for x in dice:
+		if x < 1 or x > 5:
+			return False
+	return True
+
+
+# Calculate the score for CATEGORY with the given DICE
+def calculate_score(category, dice):
+	match category:
+		case 'Ones':
+			return dice.count(1)
+		case 'Twos':
+			return dice.count(2) * 2
+		case 'Threes':
+			return dice.count(3) * 3
+		case 'Fours':
+			return dice.count(4) * 4
+		case 'Fives':
+			return dice.count(5) * 5
+		case 'Sixes':
+			return dice.count(6) * 6
+		case 'One Pair':
+			for i in range(6, 0, -1):
+				if dice.count(i) >= 2:
+					return i * 2
+			return 0
+		case 'Two Pairs':
+			if number_of_pairs(dice) != 2:
+				return 0
+
+			# Sum all of the pairs.  There are only 5 dice, so it is not
+			# possible that we have more than 2 pairs.
+			n = 0
+			for i in range(6, 0, -1):
+				if dice.count(i) >= 2:
+					n += i * 2
+			return n
+		case 'Three of a Kind':
+			for i in range(6, 0, -1):
+				if dice.count(i) >= 3:
+					return i * 3
+			return 0
+		case 'Four of a Kind':
+			for i in range(6, 0, -1):
+				if dice.count(i) >= 4:
+					return i * 4
+			return 0
+		case 'Small Straight':
+			if set(dice) == {1, 2, 3, 4, 5}:
+				return 15
+			return 0
+		case 'Large Straight':
+			if set(dice) == {2, 3, 4, 5, 6}:
+				return 20
+			return 0
+		case 'Full House':
+			# If there are 2 pairs, but only 2 different dice, it means (because
+			# there are only 5 dice total) that we have a full house
+			if len(set(dice)) == 2 and number_of_pairs(dice) == 2:
+				return sum(dice)
+			return 0
+		case 'Chance':
+			return sum(dice)
+		case 'Yatzy':
+			if len(set(dice)) == 1:
+				return 50
+			return 0
+
+
+# Calculate the total score factoring in the bonus
+def calculate_total_score(scores):
+	n = sum(x for x in scores.values() if x != -1)
+	upper_section = (
+		scores['Ones'] +
+		scores['Twos'] +
+		scores['Threes'] +
+		scores['Fours'] +
+		scores['Fives'] +
+		scores['Sixes']
+	)
+	if upper_section >= 63:
+		n += 50
+	return n
+
+
+# Check if the game is over (because the player has filled in the entire score
+# sheet)
+def game_is_over(scores):
+	return -1 not in scores.values()
+
+
+# Main game loop
+def main():
+	print('Enter the players name or ‹ENTER› if all names have been entered.')
+
+	# Read the players’ names
+	names = []
+	scores = {}
+
+	while True:
+		name = input('Name => ').strip()
+		if name == '':
+			break
+		names.append(name)
+		scores[name] = {
+			'Ones':            -1,
+			'Twos':            -1,
+			'Threes':          -1,
+			'Fours':           -1,
+			'Fives':           -1,
+			'Sixes':           -1,
+			'One Pair':        -1,
+			'Two Pairs':       -1,
+			'Three of a Kind': -1,
+			'Four of a Kind':  -1,
+			'Small Straight':  -1,
+			'Large Straight':  -1,
+			'Full House':      -1,
+			'Chance':          -1,
+			'Yatzy':           -1,
+		}
+
+	if len(names) == 0:
+		print('No players found!  Exiting…')
+		sys.exit(0)
+
+	# Check if the game is over using the score sheet of the first player
+	while not game_is_over(scores[names[0]]):
+		for player in names:
+			# Initialize variables
+			score = calculate_total_score(scores[player])
+			rolls_left = 2
+			dice = [random.randint(1, 6) for _ in range(5)]
+
+			# Clear the screen and print a header, then ask which dice to reroll
+			# and reroll if appropriate
+			while rolls_left > 0:
+				clear_screen()
+
+				print(f'Current score for {player}: {score}')
+				print(f'Your current dice: {dice}\n')
+				print(f'Which dice (1–5) would you like to reroll?  (Rolls left: {rolls_left})')
+				print('Enter the indicies space-separated or press ‹ENTER› to keep all\n')
+
+				while True:
+					xs = []
+					s = input('Dice => ').strip()
+					if s == '':
+						break
+
+					xs = s.split(' ')
+					try:
+						xs = [int(x) for x in xs]
+					except ValueError:
+						print('Invalid dice given.  Please try again!')
+					else:       # If there was no exception
+						if dice_are_valid(xs):
+							break
+						print('Invalid dice given.  Please try again!')
+
+				if xs == []:
+					break
+
+				# We do x - 1 because the list starts at 0, but the user will be
+				# counting from 1.
+				for x in xs:
+					dice[x - 1] = random.randint(1, 6)
+
+				rolls_left -= 1
+
+			# Show the possible categories that the player can select, and
+			# prompt them for a category to pick
+			clear_screen()
+			player_scores = scores[player]
+
+			print(f'Current score for {player}: {score}')
+			print(f'Your current dice: {dice}\n')
+
+			print('Your score sheet:')
+			for category in player_scores:
+				n = player_scores[category]
+				if n == -1:
+					n = '-'
+				print(f'{category}: {n}')
+			print()
+
+			print('Select a category:')
+
+			i = 1
+			index_to_category_name = {}
+
+			for category in player_scores:
+				if player_scores[category] == -1:
+					print(f'{i}. {category}')
+					index_to_category_name[i] = category
+					i += 1
+			print()
+
+			while True:
+				try:
+					selected_category = int(input('Category => '))
+				except ValueError:
+					print('Invalid category number.  Please try again!')
+				else:
+					if selected_category in index_to_category_name:
+						break
+					print('Invalid category number.  Please try again!')
+			category_name = index_to_category_name[selected_category]
+
+			player_scores[category_name] = calculate_score(category_name, dice)
+
+	clear_screen()
+	print('Game Over!\n')
+	print('Leaderboard:')
+
+	total_scores = []
+	for player in names:
+		pair = [
+			calculate_total_score(scores[player]),
+			player,
+		]
+		total_scores.append(pair)
+
+	total_scores.sort(reverse=True)
+
+	for pair in total_scores:
+		print(f'{pair[1]}: {pair[0]}')
+
+	print()
+	input('Press any key to exit...')
+
+main()