WEBVTT 00:00.890 --> 00:07.200 Are now finally ready to start making games we're starting off fairly easy with this game so that we 00:07.200 --> 00:10.110 can build our confidence when programming. 00:10.110 --> 00:16.850 But the programs will start really picking up in complexity after this. 00:16.850 --> 00:25.410 So do what I outlined in the first section which is to really understand the problem. 00:25.680 --> 00:34.140 So let's go through this and it says create a program called Number guesser error be a secret number 00:34.200 --> 00:38.520 that is set at the start of the program without any user input. 00:38.520 --> 00:44.820 So right away this tells me that we need a variable 00:48.070 --> 00:55.130 that stores the secret number right. 00:56.610 --> 01:00.540 So what we're doing is really just making notes for now. 01:00.990 --> 01:05.910 So in halves can we have something to work with in the future. 01:06.510 --> 01:10.260 So the secret number should be picked from a certain range. 01:10.260 --> 01:12.100 Sue does this mean. 01:12.180 --> 01:19.390 So it doesn't say what the range is so I guess that means we could make it up ourselves. 01:19.650 --> 01:28.200 So for our range Riskin to say it's from 0 to 100 so we're going to pick in a secret number from between 01:28.200 --> 01:29.790 zero to 100. 01:32.630 --> 01:41.100 The range should be output to the player and the player should be prompted to enter his guess that the 01:41.870 --> 01:45.150 prompt should show how many guesses the player has left. 01:45.170 --> 01:50.420 So again we need variable 01:52.970 --> 01:59.210 that stores the number guesses. 01:59.580 --> 02:02.510 Clare laughed. 02:04.760 --> 02:12.290 The player will then enter his guess if the guess is too high then the game will output that the guess 02:12.290 --> 02:18.450 is too high if the guess is too low then the game will output that the guess was too low. 02:18.470 --> 02:34.120 So I think we will also want variable that oil Store Players guess right because we need to compare 02:34.120 --> 02:34.540 it. 02:34.570 --> 02:38.760 This is this is saying we need to compare it to the secret number 02:41.960 --> 02:47.010 said the player player only has a certain number of guesses right here. 02:47.030 --> 02:55.780 He knew this the number of guesses should be based on the range of the secret number. 02:55.780 --> 03:00.210 So let's talk about that number range a little bit more. 03:00.360 --> 03:04.690 So we have the range at zero to 100. 03:04.690 --> 03:08.090 So what would be the optimal guessing strategy. 03:08.830 --> 03:13.270 Well what you'd really want to do is just guess the middle every time. 03:13.270 --> 03:13.630 Right. 03:13.630 --> 03:24.980 So the middle from 0 to 100 let's say be 50 and then that way whatever the outcome Beav either cut the 03:24.980 --> 03:29.260 range in half or we got the answer right. 03:29.540 --> 03:40.140 So if he gets 50 and it was too high let's say then we cut out 51 through a 100. 03:40.160 --> 03:43.420 So that's like half the range gone. 03:43.760 --> 03:49.410 And then if we do that again say we'll guess 25 right. 03:49.410 --> 03:56.850 That's from 0 to 49 right then that that'll cut out whatever the outcome is. 03:57.230 --> 03:58.750 OK point five yeses. 03:58.760 --> 04:01.830 That's half the range again right. 04:01.880 --> 04:07.610 So how many yeses would we need given an upper bound. 04:07.610 --> 04:07.840 Right. 04:07.880 --> 04:12.970 This 100 here well it's actually the long base too. 04:12.980 --> 04:15.530 So if you remember your math class. 04:15.530 --> 04:16.160 Right. 04:16.490 --> 04:29.650 So the long base to of a hundred is roughly kind of roughly six point six for something like this. 04:29.840 --> 04:39.430 So we'll just kind of you know fudge it to be like the ceiling of that or something like seven say day 04:39.550 --> 04:42.700 was kind of round up. 04:43.080 --> 05:06.500 So the number of guesses will be the log base two of the upper range. 05:06.930 --> 05:12.820 See how see why the understanding. 05:12.830 --> 05:19.930 The problem is so important and this really gives us the information that we need to start. 05:20.100 --> 05:25.950 So any wrong guess will we will document the number of guesses left. 05:25.980 --> 05:26.430 OK. 05:26.500 --> 05:34.290 And since the game ends by saying what the secret number was regardless of if the player guessed the 05:34.290 --> 05:35.180 right number. 05:35.300 --> 05:36.110 OK. 05:36.160 --> 05:40.860 So we just have to output the secret number at the end. 05:40.980 --> 05:47.060 So when the game is over the player should be prompted if you'd like to play again. 05:47.070 --> 05:51.090 So is going to this is going to be very important in the next lecture. 05:51.390 --> 05:55.320 And if yes the secret number should change. 05:55.370 --> 05:57.710 Kate we don't know how to do that yet. 05:57.810 --> 06:11.490 So in a rage How do we change secret number if it's not. 06:11.550 --> 06:14.830 Remember we're not putting it from the user. 06:14.850 --> 06:21.780 So and any input errors by the player should have proper handling. 06:21.900 --> 06:22.530 OK. 06:23.550 --> 06:31.840 So this is a good start for now and the next lecture we will actually start really solving the problem.