# poker4

 Author pyfex Submission date 2011-07-06 10:04:02.007233 Rating 6621 Matches played 4367 Win rate 69.57

Use rpsrunner.py to play unranked matches on your computer.

## Source code:

``````# See http://overview.cc/RockPaperScissors for more information about rock, paper, scissors

import random
import operator
import collections

if input == "":
rps = ['R', 'P', 'S']
score = {'RR': 0, 'PP': 0, 'SS': 0, 'PR': 1, 'RS': 1, 'SP': 1,'RP': -1, 'SR': -1, 'PS': -1,}
encode = { 'RR': 'a', 'PP': 'b', 'SS': 'c', 'PR': 'd', 'RS': 'f', 'SP': 'g','RP': 'h', 'SR': 'i', 'PS': 'j',}

def counter_prob(probs):
weighted_list = []
total = (probs['R'] + probs['S'] + probs['P'] + .0) * 2
for h in rps:
weighted = 0
for p in probs.keys():
points = score[h+p] + 1
prob = probs[p]
weighted += points * prob
weighted_list.append((h, weighted))
total += weighted
best, best_perc = max(weighted_list, key=operator.itemgetter(1))
best_perc /= total
return best, best_perc

hist = collections.deque()
poker = collections.defaultdict(lambda: 1)
output = random.choice(rps)
probs = {}
nothrows = 0
played = 0
total_score = 0
else:
total_score += score[output + input]
nothrows += 1
for i in range(1, 6):
pokerkey = "".join(sorted(list(hist)[-i:]))
poker[pokerkey+input] += 1
hist.append(encode[output+input])
if len(hist) > 5:
hist.popleft()
probs = {'R': 1, 'P': 1, 'S': 1}
for i in range(1, 6):
pokerkey = "".join(sorted(list(hist)[-i:]))
for t in rps:
probs[t] *= poker[pokerkey+t]

output, percentage = counter_prob(probs)
else:
output = random.choice(rps)``````