gistfile1.py

import random
import pprint
import sys


# 7 Prisoners, 1 designated counter
prisoners = [
    {"seen": False, "is_counter": False, "messaged": False},
    {"seen": False, "is_counter": False, "messaged": False},
    {"seen": False, "is_counter": False, "messaged": False},
    {"seen": False, "is_counter": False, "messaged": False},
    {"seen": False, "is_counter": False, "messaged": False},
    {"seen": False, "is_counter": False, "messaged": False},
    {"seen": False, "is_counter": True, "count": 0},
]

# Control and message bits (two switches)
control = random.choice(range(2))
message = random.choice(range(2))
init_control = control
init_message = message

tries = 0
while True:
    tries += 1
    prisoner = random.choice(prisoners)


    if not prisoner['seen']:
        prisoner['seen'] = True
        control = 0

    else:
        if prisoner['is_counter']:
            if message:
                # Someone set this bit, store and clear it
                prisoner['count'] += 1
                if prisoner['count'] == 6:
                    print "Found all!"
                    print "Initial state: %s %s" % (init_control, init_message)
                    print "Num tries: %s" % tries
                    print "----------------"
                    pprint.pprint(prisoners)
                    sys.exit()
            control = 1
            message = 0
        elif not prisoner['messaged']:
            if control and not message:
                prisoner['messaged'] = True
                message = 1