Red Black sim

import random

def playgame(trials):

    wins = 0
    iterations = 0
    while True:
        iterations = iterations + 1
        if iterations > trials:
            break
        deck = []
        for i in range(0, 52):
            if i < 26:
                deck.append('R')
            else:
                deck.append('B')

        random.shuffle(deck)

        redsleft = 26
        blacksleft = 26
        betnext = 0
        for i in range(0, 52):

            nextcard = deck.pop(0)

            if nextcard == 'R':
                if betnext == 1:
                    wins = wins + 1
                    betnext = 0
                    break
                redsleft = redsleft - 1
            elif nextcard == 'B':
                if betnext == 1:
                    betnext = 0
                    break
                blacksleft = blacksleft - 1
            else:
                print "Surprise Motherfucker!"
                exit()

            if (redsleft < 2) or ((redsleft - 1) // blacksleft == 1):
                betnext = 1

    return wins


while True:
    try1 = raw_input("\nEnter number of trials:  ")
    try:
        trials = int(try1)
    except:
        print "\n\nPlease enter a valid whole number.\n"
    else:
        if trials < 1:
            print "\n\nPlease enter a number greater than 0.\n"
        else:
            break

wins = playgame(trials)

print "\n\nTotal trials:  " + str(trials) + "\nTotal wins:  " + str(wins) + "\nTotal losses:  " + str(trials - wins) + "\nWin percentage:  " + str(float(wins * 100 / trials)) + "%"


import getpass
input3 = getpass.getpass(prompt="\n\nPress enter to exit")

exit()