WEBVTT 00:00.760 --> 00:07.430 So now let's actually start implementing everything that we've done so far. 00:07.840 --> 00:14.370 So how I usually like to start is the right kind of the main function. 00:14.410 --> 00:20.800 So it's the do while loop that we did up here. 00:20.800 --> 00:26.060 This will be our main function is do play the game while we want to play again. 00:26.190 --> 00:28.510 OK so while 00:31.500 --> 00:41.100 say want to play again I know I haven't declared the functions yet but we'll do that in just a moment 00:41.100 --> 00:42.500 here. 00:42.640 --> 00:43.730 Clay. 00:46.000 --> 00:51.130 That's going to be our main function actually. 00:51.290 --> 01:02.670 It's also going to have declare in when we make the core functions we should always think about what 01:03.690 --> 01:05.280 it should have. 01:05.280 --> 01:11.340 So play game really doesn't return anything and it doesn't need anything actually. 01:11.430 --> 01:15.480 So should be fine like this. 01:15.480 --> 01:19.860 Want to play again though will return either true or false right. 01:19.890 --> 01:27.230 Whether that player wants to play again or not want to play it again. 01:28.110 --> 01:30.190 And it won't have any arguments. 01:30.260 --> 01:34.250 OK so we're not going to have any any arguments for want to play yet. 01:34.250 --> 01:35.670 Does doesn't matter. 01:37.110 --> 01:40.290 So that's it for the main loop. 01:40.290 --> 01:43.840 Let's go to the play game function. 01:44.380 --> 01:46.350 It's got a copy both of these 01:50.670 --> 01:52.830 skin paste them and here 01:58.450 --> 02:03.630 and that stub out the want to play it again by returning false. 02:03.630 --> 02:08.380 For now we're going to implement sensate to do implement each 02:12.780 --> 02:16.340 so for the play game. 02:16.340 --> 02:25.190 We know how this works so we set the secret number the set the number guesses and then we do the do 02:25.190 --> 02:32.200 while loop and prompt user to get that gas and then check the guess and so on. 02:32.450 --> 02:34.610 We've already solved the problem. 02:34.610 --> 02:40.330 Now we just need to translate this into code so let's do that. 02:41.000 --> 02:46.510 So our secret number sorry is just an integer right. 02:46.530 --> 02:55.060 Secret number and it said to set the secret number to some known value for now k. 02:55.220 --> 03:06.380 So we're going to say it's 65 say k and then our number since a number of tries. 03:08.290 --> 03:15.520 We said that the number of tries should be the log base 2 of the upper bound. 03:15.550 --> 03:18.260 So let's define our upper bound. 03:18.720 --> 03:24.010 It's a contest in which for this 03:26.990 --> 03:28.830 and a log base 2. 03:28.860 --> 03:32.560 So we don't have this function. 03:32.610 --> 03:35.600 And we probably don't know how to write it either. 03:35.880 --> 03:49.960 But thankfully if we include sci math sci math actually has this function so thankfully we don't have 03:49.960 --> 03:52.670 to rate ourselves so you say log. 03:52.990 --> 03:59.990 Just log to of a paper about Hey that's it. 04:00.060 --> 04:02.780 In fact it even has the ceiling function. 04:02.820 --> 04:09.520 See all this. 04:09.680 --> 04:11.170 So there you go. 04:12.360 --> 04:18.090 That's our number of guesses so we always know how many guesses we should have. 04:18.090 --> 04:26.760 So the next part is to do the do while loops do they usually like to write the condition first. 04:26.760 --> 04:38.690 So while not is game over or so we know we have a function called is game over at here. 04:38.870 --> 04:45.450 So we will we should declare which. 04:46.100 --> 04:47.830 And it's game over. 04:47.840 --> 04:50.680 Returns true or false right. 04:50.690 --> 04:51.820 That's the condition. 04:51.890 --> 04:54.370 Is Game over. 04:55.420 --> 04:56.820 Yes. 04:57.550 --> 05:00.760 And we don't know if what it takes yet. 05:01.120 --> 05:02.430 Well actually that's not true. 05:02.440 --> 05:04.000 We actually do know it. 05:04.030 --> 05:07.690 If we go down here we see. 05:07.850 --> 05:11.040 So here's our kind of definition of it. 05:11.920 --> 05:18.880 And has the number of guesses left the players guess and the secret number right. 05:18.880 --> 05:22.040 These were all things that we said should be variables. 05:22.060 --> 05:26.490 So in fact we do know what should be here it should be secret number 05:30.190 --> 05:34.600 he number of tries. 05:35.470 --> 05:36.560 Left right. 05:37.810 --> 05:41.150 In the current player yes. 05:41.290 --> 05:41.820 Yes. 05:41.920 --> 05:44.950 This K 05:47.850 --> 05:52.840 is copy that and put it below. 05:52.860 --> 05:54.180 I want to play again. 05:55.360 --> 05:56.110 All implement. 05:56.120 --> 05:58.000 Want to play again soon. 06:00.590 --> 06:04.430 So you don't have to guess at since I just find the guess 06:06.980 --> 06:08.080 zero for now. 06:12.530 --> 06:15.620 And that should be secret number 06:18.650 --> 06:22.580 number tries and guess 06:26.310 --> 06:29.080 and in fact we can implement this right now. 06:29.160 --> 06:32.850 Just turn the secret number 06:38.620 --> 06:47.760 is equal to that guess guess or number of tries. 06:49.060 --> 06:51.180 Is equal to zero. 06:52.290 --> 06:54.950 Or could say less than or equal to zero. 06:55.050 --> 06:55.370 All 06:58.670 --> 07:00.040 doesn't matter. 07:02.270 --> 07:06.490 So that is game over. 07:06.660 --> 07:08.490 So the next part. 07:08.640 --> 07:14.940 And see I'm not really doing everything in order because I don't need to anymore because I know I know 07:14.940 --> 07:17.880 how this all works because I've already solved problems. 07:17.880 --> 07:22.600 I can kind of do it in whatever order I really choose. 07:22.630 --> 07:39.720 So we said that we want a function for getting the gas so gas and if you get something you're going 07:39.720 --> 07:50.240 to return the values are probably going to return an integer to get gas in here it's said we should 07:50.240 --> 07:57.290 output the number of guesses left so it should take the number of tries. 07:57.320 --> 07:57.850 Right. 07:59.710 --> 08:05.850 This K is back up here. 08:07.460 --> 08:17.740 He should return an integer and get number or get gas. 08:17.810 --> 08:20.430 It takes the number of tries 08:22.960 --> 08:23.470 this 08:26.880 --> 08:28.200 is copy 08:30.470 --> 08:31.190 this 08:35.680 --> 08:40.160 is he's down here. 08:40.350 --> 08:44.380 So let's actually implement this one right now. 08:47.280 --> 09:02.610 The should be have the inputs that gas storage and then remember had the failure here. 09:03.810 --> 09:05.870 And then we do like the do while loop. 09:05.870 --> 09:12.670 See because they could mess up all of the press like F instead of 10 or something. 09:12.710 --> 09:16.110 So for do 09:18.750 --> 09:25.300 while while there's still a failure rate and this before 09:27.840 --> 09:29.970 failure. 09:30.140 --> 09:35.420 False it's always false of the loop. 09:35.830 --> 09:46.220 And then we're are going to output these enter your guess and we have to say how many guesses you have 09:46.220 --> 09:46.750 left. 09:46.760 --> 09:52.070 A number of guesses laughs. 09:55.850 --> 09:58.250 The number of tri 10:06.850 --> 10:08.730 get I guess 10:13.460 --> 10:16.410 so they should all look very familiar to you. 10:16.420 --> 10:17.250 Right. 10:17.320 --> 10:21.910 And this couple of times now it's clear 10:24.860 --> 10:29.460 we need a constant shrink. 10:29.490 --> 10:34.470 In for snoring all characters 10:37.070 --> 10:38.600 to every launch 10:43.140 --> 10:44.850 see it nor 10:47.450 --> 10:56.710 no more sure it's an edge up until the enter key. 11:00.400 --> 11:07.510 SEE out input air please 11:09.920 --> 11:11.540 try again 11:17.590 --> 11:21.350 this and we have to say that there was a failure here. 11:21.430 --> 11:27.890 This is not OK. 11:28.070 --> 11:35.270 And then at the end it's done some sort of turn the guess because we know at this point that the guess 11:35.270 --> 11:36.240 is valid. 11:36.410 --> 11:36.930 Right. 11:38.600 --> 11:41.320 Because he exited the failure. 11:41.540 --> 11:44.630 While that while it scary. 11:44.810 --> 11:46.250 So that's good guess. 11:46.250 --> 11:49.160 So we've gotten the so what's next. 11:49.900 --> 11:52.080 So got the guess. 11:52.090 --> 11:54.580 That's kind of three and four here. 11:54.580 --> 11:58.830 And then check to see if the guess is he called to the secret number. 11:58.970 --> 11:59.480 OK. 12:00.410 --> 12:07.040 So you going to say if the guess is not equal to the number. 12:12.420 --> 12:21.420 K because up here said there's really only one case so the case is if it's not equal to the secret number 12:22.530 --> 12:35.040 so then we'll temperament the number of guesses left so you each hear number of tries left is minus 12:35.040 --> 12:43.160 minus remember that the decrement operator minus minuses one off the number. 12:43.170 --> 12:54.880 Or the current tally K and then check to see if the guess was higher or lower than the secret number. 12:54.880 --> 12:58.560 So let's do that. 12:58.570 --> 13:03.940 So if the guess is greater than the secret number 13:08.390 --> 13:10.250 then we will just output 13:14.990 --> 13:18.790 your guess was too high. 13:20.820 --> 13:21.750 OK. 13:22.110 --> 13:27.390 Else and we don't need another case right because we're very checked to see if they're equal and they're 13:27.390 --> 13:28.490 not. 13:28.500 --> 13:34.780 So we know that if it's not greater than Then it must be less then. 13:35.160 --> 13:35.590 So 13:41.730 --> 13:45.190 your guess is to 13:48.710 --> 13:48.970 each 13:52.220 --> 14:04.940 time it's just an exclamation point in your. 14:05.020 --> 14:13.270 So while the game's not over so we're almost done with the play game function but we just need to display 14:13.270 --> 14:14.640 the results. 14:16.580 --> 14:19.860 And what should display results take. 14:19.870 --> 14:29.100 Well if you looked back here we need to see what we need to see her number for sure. 14:30.030 --> 14:30.690 OK. 14:31.120 --> 14:38.780 But there's something here that we didn't really go over and it's this If the player got it. 14:38.830 --> 14:41.430 So how do we know if the player got it or not. 14:41.890 --> 14:50.490 Well if the number of tries is greater than zero then we know they must have gotten it right. 14:50.800 --> 14:56.450 So we're going to need the number of tries as well. 14:56.570 --> 15:00.070 So just say secret number 15:04.890 --> 15:07.860 and the number of tries. 15:11.190 --> 15:18.340 This is really the number of troops left so need to declare this function 15:22.510 --> 15:26.290 and it doesn't return anything because it is going to output something. 15:26.390 --> 15:28.280 So it's way 15:30.990 --> 15:33.930 so inch 15:37.720 --> 15:38.650 secret number 15:41.090 --> 15:52.780 in the mirror tri's and so copy us. 15:53.290 --> 15:54.440 Hello here. 15:56.760 --> 15:59.790 Weren't too much about the organization of it evidence. 15:59.800 --> 16:02.530 Pretty small program so. 16:02.710 --> 16:05.600 So how did this work. 16:08.120 --> 16:12.590 So if the if the player got it it would just print out that they got it. 16:12.590 --> 16:18.750 And the secret number and if they didn't and would print out that they didn't answer number. 16:18.920 --> 16:22.160 If so they got it. 16:22.160 --> 16:30.450 If the number of tries is greater It's greater than zero. 16:30.480 --> 16:31.400 Right. 16:31.500 --> 16:32.880 So they have tried left 16:37.190 --> 16:41.960 and this is the ouch. 16:42.100 --> 16:42.740 You got it 16:45.480 --> 16:46.490 was 16:53.360 --> 16:53.910 easy. 16:54.060 --> 16:54.420 Number 16:58.840 --> 16:59.520 else 17:04.150 --> 17:06.350 you didn't get it. 17:11.620 --> 17:12.880 It was 17:15.720 --> 17:16.660 this number 17:19.750 --> 17:22.910 that K.. 17:23.500 --> 17:29.150 So really just following our kind of template that we laid out here. 17:29.350 --> 17:30.730 OK. 17:31.480 --> 17:34.370 So what do we have left here. 17:35.240 --> 17:36.930 So we have to implement. 17:36.950 --> 17:39.280 We want to play again. 17:40.070 --> 17:41.380 And each 17:45.150 --> 17:46.600 It's really I think. 17:46.870 --> 17:47.990 Yeah. 17:48.130 --> 17:50.170 So let's do that now. 17:50.230 --> 17:53.060 So we already know how this works. 17:54.310 --> 17:58.090 So it's fine actually we're going to 18:03.130 --> 18:06.540 cut that and put this in global scope. 18:10.080 --> 18:17.570 So we can use it for both functions of the get gas and watch play in. 18:17.610 --> 18:21.860 So here how I want we want to play. 18:21.870 --> 18:28.690 Going to work is I really want them to input a character. 18:28.800 --> 18:36.950 So we're going to say that's the inputs and again we're going to have this failure. 18:37.560 --> 18:46.820 And again to do so while failure thing for 18:49.450 --> 18:52.700 an We're going to set the input or the failure. 18:52.700 --> 19:06.300 Sorry to be false and it's going to prompt the user would you like to again 19:10.360 --> 19:16.160 get the input Again this could fail right. 19:16.180 --> 19:22.140 So if we see and fail 19:26.900 --> 19:33.290 season on it and send a clear and and no more 19:36.470 --> 19:40.380 no more chores. 19:44.150 --> 19:44.920 You on 19:49.880 --> 19:50.480 see 19:54.380 --> 19:56.480 input each error. 19:59.330 --> 20:03.160 These try again. 20:06.140 --> 20:09.950 There isn't failure in this case. 20:17.640 --> 20:19.730 And just return 20:23.530 --> 20:27.570 the if there if we said 20:31.730 --> 20:38.500 they said why can't they input a character why. 20:38.540 --> 20:44.240 And in fact let's just give them a helping hand here. 20:45.300 --> 20:45.840 This 20:50.780 --> 20:54.890 so if they type why it will return that they do want to play again. 20:54.890 --> 21:00.030 In fact if they type anything else they won't want to play them. 21:01.610 --> 21:02.420 So 21:04.910 --> 21:08.960 let's take a look at this one more time. 21:09.320 --> 21:11.980 We're just really. 21:12.070 --> 21:22.650 So let's run this in over. 21:22.780 --> 21:28.080 So please enter your gas number of guesses left is seven right. 21:28.170 --> 21:37.340 So one thing actually we didn't do is output the range. 21:37.560 --> 21:41.140 So you do that right here. 21:41.170 --> 21:42.350 See out 21:45.250 --> 21:54.490 the range of the number is between 0 and onward. 21:54.760 --> 22:07.090 K. stratas in K. So the range of the number is between zero and a hundred and you have seven guests 22:07.100 --> 22:11.350 left so eight gas is too low. 22:11.370 --> 22:20.300 And see updated that we have only six tri's left so let's in this test this whole thing. 22:20.640 --> 22:25.980 And this time we're going to test to see if we can completely fail at it. 22:25.980 --> 22:43.360 So 90 I 100 Do I say 32 to high 3 9 0 to low and then it said you didn't get it right. 22:43.390 --> 22:45.130 It was 65 k. 22:45.160 --> 22:47.140 So that case is working. 22:47.380 --> 22:57.040 And say I do want to play and notice that it outputs the range again because we're in the do while loop 22:57.250 --> 23:06.010 and call play game and play game again we'll do all this code again. 23:06.010 --> 23:13.350 So while in this era and this time we actually try to get nine to 23:16.020 --> 23:18.040 say 65. 23:18.420 --> 23:18.950 You got it. 23:18.980 --> 23:25.670 Sixty five and say no and exit it. 23:25.690 --> 23:26.930 So there you go. 23:28.160 --> 23:30.150 This program is working. 23:30.240 --> 23:39.800 So gratulations if you followed along this is your very first game in C++ and in the next lecture I 23:39.800 --> 23:43.190 went to sort of change just a little bit. 23:43.190 --> 23:52.930 So if you remember we wanted to be able to change the secret number every time you play the game. 23:53.000 --> 23:56.120 So we're going to see how we can solve that problem.