[Tutor] Newbie Q's

[alan.gauld@bt.com]

> I have two quick questions for you. First, if I have a
> list made up of integers, is there a simple command to
> let me find the sum of the integers (and assign the
> value to a variable)? 

The most direct way is with a loop:

result = 0
for num in numlist:
    result += num

Or using Pythons reduce function:

result = reduce(operator.add, numlist)

Which does the same thing.

> The biggest difficulty I'm having is dealing with
> aces, which can be valued at 1 or 11. I thought I had
> everything figured out, until a hand came up that had
> two aces in it :-) I'm sure many people have tried
> making this kind of a program. How did you (or would
> you) deal with this aspect of the program? 

Special cases need special code. For blackjack you would 
count the Ace as 11 if the total was <= 21 else count them 
as 1... 
So something like the following untested code:

def AddCards(cardlist):
    tot = reduce(operator.add, cardlist)
    if  tot > 21: #too high
       while 11 in cardlist:   #do we have high aces?
         if tot-10 <= 21:      # total too high so use low ace
           pos = cardist.index(11)
           cardlist[pos] = 1   # change from 11 to 1
           tot = reduce(operator.add, cardlist)
    return tot

Theres probably a neater way but that might help...

Alan g