Python simulation of Chutes and Ladders

cl.py

import sys
import numpy as np

"""
	Simulate chutes and ladders.
	Reports the number of moves for 1-player to reach the end,
	followed by the list of rolls that player had.

	Run as follows for 100000 games with 1 player. Report the total
	number of moves made by the winning player:

		python cl.py 100000 1 

	1000 games with 4 players

		python cl.py 1000 4

"""

chutes = {
	16:6, 47:26, 49:11, 56:53, 62:19,
	64:60, 87:24, 93:73, 95:75, 98:78
}

ladders = {
	1:38, 4:14, 9:31, 21:42, 28:84,
	36:44, 51:67, 71:91, 80:100
}


def roll(sides=20):
	"""
	Roll a fair die of arg(sides) sides
	"""
	return np.random.randint(1,sides+1)

def initialize_game(num_players):
	"""
	Reset the game. All players at position 0.
	"""
	p_curr = {}
	p_moves = {}
	p_rolls = {}
	for p in range(num_players):
		p_curr[p] = 0
		p_moves[p] = 0
		p_rolls[p] = []
	return p_curr, p_moves, p_rolls

num_games = int(sys.argv[1])
num_players = int(sys.argv[2])
end = 100

for game in range(num_games):

	# setup the game
	winner = None
	total_moves = 0
	p_curr, p_moves, p_rolls = initialize_game(num_players)
	
	while winner is None:
		for p in range(num_players):
			
			r = roll()
			total_moves += 1
			p_moves[p] += 1
			p_curr[p] += r
			p_rolls[p].append(r)

			# house rules. land on or exceed 100.
			if p_curr[p] >= end:
				winner = p
				break

			# did the current player land on a chute?
			if p_curr[p] in chutes:
				p_curr[p] = chutes[p_curr[p]]
			# did the current player land on a ladder?
			elif p_curr[p] in ladders:
				p_curr[p] = ladders[p_curr[p]]
				if p_curr[p] == end:
					winner = p
					break

	print str(winner) + '\t' + str(p_moves[winner]) + '\t' + str(total_moves) + \
		'\t' + ','.join(str(r) for r in p_rolls[winner])

run.sh

python cl.py 10000 1 | head | column -t
winning_player  winners_move_cnt  tot_moves  winners_moves
1               36                36         6,3,6,6,5,2,5,6,5,2,3,2,3,1,2,6,5,6,2,5,1,5,5,4,6,2,2,5,1,1,4,6,5,6,1,5
1               12                12         3,3,6,1,4,6,5,2,5,3,3,5
1               59                59         5,5,2,2,3,4,6,5,1,1,3,2,1,4,4,1,3,2,4,4,4,2,1,5,3,6,5,1,3,6,6,6,5,6,2,2,5,6,2,1,3,4,5,4,3,3,4,1,1,5,5,3,2,5,6,6,6,3,6
1               12                12         1,6,2,2,6,2,6,4,5,3,4,5
1               37                37         5,1,4,3,6,5,5,6,4,3,4,3,5,4,6,1,5,1,6,5,4,6,5,3,3,1,4,6,6,3,1,2,5,2,6,1,2
1               24                24         2,1,2,5,1,6,1,3,1,5,3,4,2,4,2,2,2,1,1,6,1,6,1,1
1               17                17         6,6,1,2,2,4,3,1,5,1,4,4,6,6,3,6,3
1               15                15         2,1,1,1,6,3,1,1,2,6,2,2,2,3,6
1               35                35         6,6,2,1,3,4,1,4,4,3,4,1,2,3,1,2,6,6,4,5,5,1,5,5,4,5,1,1,3,5,6,6,6,1,4

# stats on number of moves:
python cl.py 100000 1 | awk 'NR>1' | cut -f 2 | stats
Total lines:		100000
Sum of lines:		3579432
Ari. Mean:		35.79432
Geo. Mean:		29.9810932680843
Median:			29
Mode:			18 (N=2857)
Anti-Mode:		178 (N=1)
Minimum:		7
Maximum:		264
Variance:		537.847395737582
StdDev:			23.191537157713