1 00:00:05,280 --> 00:00:08,039 So how did you get on? There are lots of ways you may have 2 00:00:08,039 --> 00:00:12,320 written your code. The real test is that it works. Alright, so let's go 3 00:00:12,320 --> 00:00:15,360 through our solution. I'm going to start with some very brief 4 00:00:15,360 --> 00:00:20,320 instructions - very brief instructions - and get the player to press enter to start. 5 00:00:20,320 --> 00:00:24,480 So let's have a go at doing that. I'm going to start down here. I'm going 6 00:00:24,480 --> 00:00:29,519 to remove this for loop - start on line 21. I'm going to type input 7 00:00:29,519 --> 00:00:35,920 parentheses double quotes Play Fizz Buzz. Full stop, 8 00:00:35,920 --> 00:00:40,640 a couple of spaces there, Press ENTER to start 9 00:00:40,640 --> 00:00:44,559 double quote right parentheses. Then we'll do a print 10 00:00:44,559 --> 00:00:48,960 parentheses for a blank line. Alright, so next we're going to use a 11 00:00:48,960 --> 00:00:52,640 while loop, and increase a counter each time the computer and the 12 00:00:52,640 --> 00:00:57,920 player says their number. On line 24, next_number 13 00:00:57,920 --> 00:01:02,620 is equal to zero. Let me move this up a little bit actually. 14 00:01:02,620 --> 00:01:04,080 And we're going to do that while loop 15 00:01:04,080 --> 00:01:10,159 that I talked about, so while next_number is less than 99 16 00:01:10,159 --> 00:01:17,600 colon, next_number plus equals one. Then on the next line, print 17 00:01:17,600 --> 00:01:23,439 parentheses fizz_buzz, and in parentheses, we're passing next 18 00:01:23,440 --> 00:01:29,820 number, so next_number. So we've initialized next_number to zero, 19 00:01:29,820 --> 00:01:33,840 then increase it by one before each of the computers goes. 20 00:01:33,840 --> 00:01:38,560 The computer generates this number and prints it on line 27. 21 00:01:38,560 --> 00:01:40,980 Alright, so now it's the player's turn. 22 00:01:40,980 --> 00:01:43,440 So we need to increment next_number again, 23 00:01:43,440 --> 00:01:47,980 and use it to calculate the correct answer. Then we get the player's input. 24 00:01:47,980 --> 00:01:53,020 Alright, so next_number plus equals one. 25 00:01:53,020 --> 00:01:56,159 Alright, then correct answer 26 00:01:56,160 --> 00:02:03,540 is equal to fizz_buzz, and we're passing next_number to that 27 00:02:03,540 --> 00:02:07,600 players_answer, on the next line, 28 00:02:07,600 --> 00:02:11,440 is equal to input parenthesis double quotes, 29 00:02:11,440 --> 00:02:14,879 Your go colon and a space, then we've got the double quote 30 00:02:14,879 --> 00:02:19,599 and the right parenthesis. Because we have to increment next number twice, 31 00:02:19,599 --> 00:02:24,080 a while loop is more suitable than a for loop. It is possible to use a for loop, 32 00:02:24,080 --> 00:02:27,200 with a step of two, but it does get a bit messy. 33 00:02:27,200 --> 00:02:30,400 If you want to try a for loop, to see the problems you get, then wait until I've 34 00:02:30,400 --> 00:02:33,120 shown you how to cheat, at the end of this video. 35 00:02:33,120 --> 00:02:37,360 To check if the player provided the correct number - or fizz, buzz or fizz buzz - 36 00:02:37,360 --> 00:02:41,360 we now need to compare the input to the value returned by our function. 37 00:02:41,360 --> 00:02:45,760 So let's do that. So we're going to type if 38 00:02:45,760 --> 00:02:52,319 players_answer is not equal to correct_answer colon. 39 00:02:52,320 --> 00:02:55,380 We need to print a message here to say they got it wrong. So print 40 00:02:55,380 --> 00:02:59,520 and in parentheses, double quotes You lose, 41 00:03:00,080 --> 00:03:06,800 the correct answer was, left and right curly braces double 42 00:03:06,800 --> 00:03:10,480 quote dot format parentheses, correct_answer 43 00:03:10,480 --> 00:03:13,280 in those parentheses, and then we're closing that off. 44 00:03:13,280 --> 00:03:16,959 Then on the next line, we need to do a break. 45 00:03:16,959 --> 00:03:21,120 They get it wrong, we need to break out of the loop. So looking at lines 26 46 00:03:21,120 --> 00:03:26,799 through 28, we increment next number before calling the fizz_buzz function. 47 00:03:26,799 --> 00:03:30,959 Inside the loop, next_number gets increased by 1 twice - 48 00:03:30,959 --> 00:03:34,159 once before the computer's response and once before checking 49 00:03:34,159 --> 00:03:37,280 what the player enters. Okay, so that should work. 50 00:03:37,280 --> 00:03:40,239 It would be nice to let the player know that they're finished, though. If we get 51 00:03:40,239 --> 00:03:43,120 to the end, the while loop will terminate normally - 52 00:03:43,120 --> 00:03:46,239 we don't break out of it. Now if you remember from the Program 53 00:03:46,239 --> 00:03:50,799 flow control in Python section, an else block can be used to execute 54 00:03:50,799 --> 00:03:53,439 code, only when the loop terminates normally. 55 00:03:53,439 --> 00:03:58,239 So let's add an else here on line 34, an else to the while statement 56 00:03:58,240 --> 00:04:05,140 on line 25; else colon print parentheses double quotes Well done, 57 00:04:05,140 --> 00:04:08,880 you reached, then left and right curly braces, 58 00:04:08,880 --> 00:04:14,000 double quote dot format and next_number in parentheses, 59 00:04:14,000 --> 00:04:17,260 and closing off that line. 60 00:04:17,260 --> 00:04:20,798 Alright, so that should be that. We're now ready to play fizz buzz 61 00:04:20,798 --> 00:04:23,120 and it's harder than it sounds. Alright, so let's run 62 00:04:23,120 --> 00:04:25,759 the program now. I'll have a couple of goes myself. 63 00:04:25,759 --> 00:04:28,880 Alright, so I'm going to start by pressing ENTER to start, 64 00:04:28,880 --> 00:04:33,680 1 Your go. The next number is 2 - that's not fizz, buzz or fizz buzz, 65 00:04:33,680 --> 00:04:37,040 so we'll put 2 there. 3, which is correct, 66 00:04:37,040 --> 00:04:42,540 because the number three is divisible by three, so I'll put four in there, buzz. 67 00:04:42,540 --> 00:04:45,919 We're up to five - five was chosen by the computer - 68 00:04:45,919 --> 00:04:50,800 so I'm gonna put six there, and of course, I screwed that up because 69 00:04:50,800 --> 00:04:54,639 six is divisible by three. Again, it's harder than it sounds if you're not 70 00:04:54,639 --> 00:04:57,199 really paying attention. Alright, so have a go yourself and see 71 00:04:57,199 --> 00:05:00,080 how far you can get on your first try. I'm a bit embarrassed to say that I only got 72 00:05:00,080 --> 00:05:02,880 up to number six. Getting to 100 actually isn't easy, 73 00:05:02,880 --> 00:05:06,479 unless you're really concentrating. Alright, so to test that we get the 74 00:05:06,479 --> 00:05:11,680 Well done message printed out on line 35 - close down the run window now - 75 00:05:11,680 --> 00:05:15,120 we're going to actually cheat a bit, because obviously, to get to 100 will take some time. 76 00:05:15,120 --> 00:05:20,400 So i'm going to comment out the input, and bind the player's answer to the correct one. 77 00:05:20,400 --> 00:05:25,280 So I'm gonna come up here to line 30. I'm going to comment that out, 78 00:05:25,280 --> 00:05:28,800 and instead what I'm going to do, is add a line under that 79 00:05:28,800 --> 00:05:36,860 and put players_answer is equal to correct_answer. 80 00:05:36,860 --> 00:05:39,840 So by doing that, the player's answer will always be correct, 81 00:05:39,840 --> 00:05:43,060 and we can test what happens when the player gets to the end. 82 00:05:43,060 --> 00:05:46,240 So if we actually run this now. 83 00:05:46,240 --> 00:05:49,680 Now I'm not suggesting that you cheat when testing your code. I've done this to 84 00:05:49,680 --> 00:05:53,120 be reasonably sure that there isn't a serious bug in the code. 85 00:05:53,120 --> 00:05:58,479 Close down that run window. Now the next step is to swap the commenting around, 86 00:05:58,479 --> 00:06:03,680 on lines 30 and 31 which I'm doing now, and to play the game properly. 87 00:06:03,680 --> 00:06:07,600 This will take a while, which is why I cheated. We've shown that there's nothing 88 00:06:07,600 --> 00:06:11,980 seriously wrong with this code. We can now spend the time to test it properly. 89 00:06:11,980 --> 00:06:14,080 Don't take shortcuts when testing. 90 00:06:14,080 --> 00:06:17,919 A quick cheat, to verify that it's possible to get to the end, is valid, 91 00:06:17,919 --> 00:06:21,039 but it's not a substitute for thorough testing. 92 00:06:21,039 --> 00:06:24,560 Alright, so have fun playing the game, and then have a go at the exercise coming up. 93 00:06:24,560 --> 00:06:28,800 I'll see you in the next video.