1 00:00:00,810 --> 00:00:04,620 Now let's move on to a hint 9. So we want to call 2 00:00:04,620 --> 00:00:07,350 calculate_score at some point in our code 3 00:00:07,920 --> 00:00:10,830 and if the computer or the user has a Blackjack 4 00:00:11,250 --> 00:00:15,390 or if the user's score is over 21, then the game is going to end. 5 00:00:15,900 --> 00:00:19,440 This might be a good time to start tidying up our code a little bit, 6 00:00:19,860 --> 00:00:22,320 because we've got our function over here, 7 00:00:23,310 --> 00:00:25,140 the calculate score function. 8 00:00:25,710 --> 00:00:29,790 And remember that you can only call a function after it's been declared. 9 00:00:30,150 --> 00:00:34,500 So for example, if I wanted to call this function over here, 10 00:00:34,860 --> 00:00:36,090 then I actually can't. 11 00:00:36,090 --> 00:00:40,710 I can't say calculate_score because it hasn't yet been declared. 12 00:00:41,310 --> 00:00:42,210 So instead, 13 00:00:42,240 --> 00:00:46,980 what I'm going to do is I'm going to take this function and I'm going to move it 14 00:00:47,220 --> 00:00:51,720 to where we dealt our cards and I'm going to collapse some of these functions so 15 00:00:51,720 --> 00:00:55,080 I can see my hints and my code a little bit easier. 16 00:00:56,040 --> 00:01:00,360 So now that I've moved my function to above the line where I want to call it, 17 00:01:00,690 --> 00:01:02,430 it's now become valid code. 18 00:01:02,970 --> 00:01:07,530 And this is the place where I want to call it because it's only after I've dealt 19 00:01:07,530 --> 00:01:12,390 the user and the computer some cards can I actually calculate their scores. 20 00:01:12,900 --> 00:01:16,740 Firstly, I want to calculate the score using the user's cards. 21 00:01:17,160 --> 00:01:22,160 So this list of cards from the user gets passed into this function and uses 22 00:01:22,800 --> 00:01:26,280 all of the logic to output some sort of score. 23 00:01:27,180 --> 00:01:29,820 And then I'm going to store that score in a variable 24 00:01:29,820 --> 00:01:31,290 which I'll call user_score. 25 00:01:32,190 --> 00:01:35,160 And I'm going to do the same thing for the computer, 26 00:01:35,190 --> 00:01:40,170 so computer_score equals calculate_score. And remember, 27 00:01:40,440 --> 00:01:45,440 it's always helpful to add a little bit of a docstring to tell ourselves and 28 00:01:45,870 --> 00:01:49,650 other programmers what this function does. Let's quickly summarize it. 29 00:01:49,650 --> 00:01:54,650 So this function is going to take a list of cards and return the score 30 00:01:57,120 --> 00:01:58,980 calculated from the cards. 31 00:02:00,780 --> 00:02:02,790 So now when I open that parentheses, 32 00:02:03,150 --> 00:02:07,200 I know that I probably have to pass in my list of cards in order to get back the 33 00:02:07,200 --> 00:02:08,032 score. 34 00:02:08,130 --> 00:02:12,480 So let's put in the computer_cards in as the inputs, 35 00:02:12,900 --> 00:02:15,690 and now we've got the user_score and the computer_score. 36 00:02:16,110 --> 00:02:18,000 So this score could equal zero 37 00:02:18,030 --> 00:02:22,890 if they got a Blackjack or it could just simply be the value of the cards that 38 00:02:22,890 --> 00:02:24,930 they hold all added up together. 39 00:02:26,070 --> 00:02:28,620 Now that we've called calculate_score 40 00:02:29,040 --> 00:02:34,040 we also want to make sure that if the computer or the user has a Blackjack 41 00:02:34,710 --> 00:02:39,450 or if the user's score is over 21, then we have to end the game. 42 00:02:40,740 --> 00:02:45,510 Let's write our if statements. If the user_score is equal to zero, 43 00:02:46,080 --> 00:02:50,130 or the computer_score is equal to zero, 44 00:02:50,760 --> 00:02:55,740 or the user_score is greater than 21, then in this case 45 00:02:55,770 --> 00:02:58,140 we're going to tell the game to end. 46 00:02:58,560 --> 00:03:03,130 So we could create a new variable called is_game_over 47 00:03:04,450 --> 00:03:08,890 and we start out with false, of course. But then when this happens, 48 00:03:08,950 --> 00:03:12,160 we're going to change that variable to true instead. 49 00:03:13,180 --> 00:03:16,960 Our is_game_over variable is just a simple boolean. 50 00:03:17,620 --> 00:03:21,100 It starts out as false and when certain conditions are met, 51 00:03:21,310 --> 00:03:25,660 then we change it to true. Now at the moment, our program is not finished. 52 00:03:25,750 --> 00:03:29,880 So it was not really obvious how we're going to be using this is_game_over 53 00:03:29,890 --> 00:03:33,220 variable. But we're setting ourselves up for the next steps. 54 00:03:33,670 --> 00:03:36,190 Now that we're tracking if the game should end, 55 00:03:36,400 --> 00:03:39,520 we can look at this value to determine what to do next. 56 00:03:39,880 --> 00:03:44,740 So that's hint 9 completed. Let's test our code and see how everything works so 57 00:03:44,740 --> 00:03:45,573 far. 58 00:03:45,820 --> 00:03:49,840 I'm going to add some print statements here so that I can see what the user's 59 00:03:49,840 --> 00:03:54,670 cards are and what the user's score is. Using an fstring 60 00:03:54,730 --> 00:03:59,470 I'm going to show your cards, so the user's cards, and the current score. 61 00:04:00,880 --> 00:04:04,810 And I'm also going to print the computers first card. 62 00:04:05,320 --> 00:04:08,350 Remember when I first explained the rules of Blackjack, 63 00:04:08,710 --> 00:04:12,220 the dealer will reveal their first card 64 00:04:12,640 --> 00:04:17,050 so you get a little bit of a clue as to what kind of hand they might have. 65 00:04:18,160 --> 00:04:21,310 So in here, we're going to insert the computer's cards 66 00:04:21,760 --> 00:04:26,470 and we're only gonna pick out the first item, so that the one at index zero, 67 00:04:26,590 --> 00:04:30,610 and we do that using a square bracket after the name of the list. 68 00:04:31,960 --> 00:04:36,220 Now let's give our program a run and see if it actually works. 69 00:04:36,820 --> 00:04:40,780 The first thing that prints is a list of our cards. 70 00:04:40,840 --> 00:04:41,920 So in our hand, 71 00:04:41,950 --> 00:04:46,180 we have a 2 and we have a 6 and 2 + 6 added together 72 00:04:46,210 --> 00:04:48,040 of course makes the score of 8. 73 00:04:48,670 --> 00:04:52,630 And then it reveals to us the computer's first card, which is a 10. 74 00:04:53,320 --> 00:04:57,730 Now we can be reasonably assured that our code is working. 75 00:04:58,330 --> 00:05:02,170 And it's a good idea to regularly test your code so that you don't wait until 76 00:05:02,170 --> 00:05:04,120 the end when they're a lot of problems 77 00:05:04,360 --> 00:05:06,790 and you don't know which part of the code is responsible.