Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated: 1 00:00:00,180 --> 00:00:00,810 All right, now 2 00:00:00,810 --> 00:00:05,280 it's time to put what you've learned into practice by clicking on the data types 3 00:00:05,400 --> 00:00:08,040 day 2.1 code challenge. 4 00:00:09,540 --> 00:00:10,470 In this challenge, 5 00:00:10,500 --> 00:00:15,450 the idea is that you are going to be given a random two-digit number, 6 00:00:15,480 --> 00:00:20,480 so something like 39, and your code that you'll write 7 00:00:21,060 --> 00:00:26,060 will be able to add the first digit to the second digit and end up with a 8 00:00:26,850 --> 00:00:31,650 numerical result. So for example, if the input was 39, 9 00:00:31,680 --> 00:00:36,000 then 3 + 9 would be equal to 12. So the output would be 12. 10 00:00:36,480 --> 00:00:39,060 And if the input was 26, 11 00:00:39,180 --> 00:00:42,420 then your code needs to print 8 to the console. 12 00:00:43,080 --> 00:00:47,100 So you're going to need to think about type checking, type conversion, 13 00:00:47,430 --> 00:00:49,710 as well as everything that you learned before. 14 00:00:50,550 --> 00:00:54,270 And then you're going to write your code below this line without changing any of 15 00:00:54,270 --> 00:00:58,140 these lines. So pause the video now and give this code challenge a go. 16 00:01:02,610 --> 00:01:07,200 All right. So how did that go? Did you manage to do it? If not, 17 00:01:07,380 --> 00:01:09,900 have a cup of tea or give yourself a little bit of a break, 18 00:01:09,900 --> 00:01:12,750 think about something else and then come back to it and try it again. 19 00:01:13,530 --> 00:01:14,110 If you've already 20 00:01:14,110 --> 00:01:17,340 given it a good go and you want to see what the solution might be, 21 00:01:17,700 --> 00:01:18,900 then follow along with me. 22 00:01:19,650 --> 00:01:23,250 So the first thing we know is that we're going to have a variable 23 00:01:23,280 --> 00:01:26,970 that's going to be equal to a two-digit number. 24 00:01:27,540 --> 00:01:30,660 But remember that that could mean anything. That could mean an integer, 25 00:01:30,660 --> 00:01:34,590 that could mean a floating-point number, that could even mean a number as a 26 00:01:34,590 --> 00:01:35,423 string. 27 00:01:35,790 --> 00:01:40,790 So it might be helpful to actually find out the data type of this two-digit 28 00:01:41,310 --> 00:01:46,200 number that we get. And to do that, we of course use the type function, all 29 00:01:46,200 --> 00:01:48,810 lowercase. And then in between the parentheses, 30 00:01:48,840 --> 00:01:52,470 we add the thing that we want to check. So it's this variable. 31 00:01:53,040 --> 00:01:56,130 And then let's go ahead and print the result into the console. 32 00:01:56,550 --> 00:02:00,390 So now let's run our code and let's type a two-digit number, 33 00:02:00,570 --> 00:02:01,590 say 56. 34 00:02:02,100 --> 00:02:07,100 and we get the result that the type of this two-digit number is a string 35 00:02:08,670 --> 00:02:13,410 because, of course, we're getting hold of this through the input function and the 36 00:02:13,410 --> 00:02:17,280 user could be typing anything into this input, a string, 37 00:02:17,310 --> 00:02:18,840 their name or a number. 38 00:02:19,290 --> 00:02:22,560 So now that we know that this variable has the datatype string, 39 00:02:22,950 --> 00:02:27,090 then you can think of a little bit about what we know we can do with strings. 40 00:02:27,330 --> 00:02:31,920 We can subscript strings, right? So if we had a string like hello, 41 00:02:32,250 --> 00:02:36,330 and we want it to get a hold of the first character, we could put zero there. 42 00:02:36,570 --> 00:02:37,860 And when I print this, 43 00:02:38,160 --> 00:02:42,120 we'll get H being selected out of this string. 44 00:02:43,050 --> 00:02:48,050 So if we know that we can subscript strings to get a hold of a particular value 45 00:02:50,130 --> 00:02:54,690 at a particular position just by using subscripting like this, 46 00:02:54,990 --> 00:02:58,020 then we can do the same with our two-digit number. 47 00:02:58,230 --> 00:03:02,950 So we could say two_digit_number, let's get hold of the first digit. 48 00:03:03,130 --> 00:03:04,030 So let's call it 49 00:03:04,030 --> 00:03:08,830 first_digit equals two_digit_number [ 50 00:03:08,860 --> 00:03:09,693 0], 51 00:03:10,120 --> 00:03:15,120 and then the second_digit could be two_digit_number [1]. 52 00:03:16,660 --> 00:03:17,493 Now, 53 00:03:17,680 --> 00:03:22,180 when I go ahead and print these two items, 54 00:03:22,210 --> 00:03:25,990 first_digit and second_digit, 55 00:03:26,440 --> 00:03:30,280 then you'll see that if I enter a number like 87, 56 00:03:30,760 --> 00:03:34,600 then my first digit is 8 and my second digit is 7. 57 00:03:35,110 --> 00:03:39,820 So now I can probably start thinking about adding those two digits together. 58 00:03:40,420 --> 00:03:40,990 For example, 59 00:03:40,990 --> 00:03:45,990 we can say that result equals first_digit plus second_digit. 60 00:03:47,200 --> 00:03:51,790 But of course, when I run this right now and I print the value of result, 61 00:03:52,270 --> 00:03:54,910 you'll see that for a number like 87 62 00:03:55,390 --> 00:04:00,340 what I will get is just a eight concatenated to seven, 63 00:04:00,520 --> 00:04:04,030 which turns it back into 87, which is not what I want at all. 64 00:04:04,390 --> 00:04:07,840 Especially after all of my hard work separating out the digits. 65 00:04:08,470 --> 00:04:11,770 What I want to do instead is to turn each of these, 66 00:04:12,070 --> 00:04:15,010 which currently has the data type of string, 67 00:04:15,190 --> 00:04:20,190 so I can demonstrate that to you by saying type of first_digit, 68 00:04:20,950 --> 00:04:24,460 you can see it is a string. 69 00:04:25,000 --> 00:04:30,000 So if I could only change first_digit and second_digit from string data types 70 00:04:31,000 --> 00:04:36,000 into an integer data type by using the type conversion that we learned about 71 00:04:37,240 --> 00:04:41,320 in the last lesson, well then once I do that, 72 00:04:41,350 --> 00:04:46,120 then this plus sign has a whole different meaning because now it's going to add 73 00:04:46,150 --> 00:04:50,260 this first_digit to the second_digit instead of concatenating it. 74 00:04:50,620 --> 00:04:53,350 So now if I go ahead and print the results, 75 00:04:55,420 --> 00:04:58,270 then you'll see that for the same number 76 00:04:59,770 --> 00:05:02,500 87, my result is now 15. 77 00:05:03,310 --> 00:05:08,140 I've now managed to achieve what the code exercise wants me to do. 78 00:05:09,560 --> 00:05:12,190 So did you manage to get it right? If not, 79 00:05:12,220 --> 00:05:15,340 go ahead and have a look at the model solution 80 00:05:15,610 --> 00:05:19,990 and I've written some comments for each line of code that walks you through each 81 00:05:19,990 --> 00:05:20,823 of the steps. 82 00:05:21,070 --> 00:05:25,930 Now notice that instead of converting the second_digit here, 83 00:05:26,380 --> 00:05:30,250 you can also do it up here, like what you see right here. 84 00:05:31,270 --> 00:05:32,950 So I have a play around with the code, 85 00:05:33,010 --> 00:05:36,520 especially if you struggled with this and didn't manage to get it right. 86 00:05:37,060 --> 00:05:40,660 And then once you've understood what's going on here line by line, 87 00:05:41,080 --> 00:05:43,300 if you need, have a look at the previous videos, 88 00:05:43,600 --> 00:05:46,390 then go back to the code challenge and attempt it again. 89 00:05:46,960 --> 00:05:50,260 And only once you're happy that you really understand everything that was 90 00:05:50,260 --> 00:05:51,610 covered in this challenge, 91 00:05:51,880 --> 00:05:54,910 then head over to the next lesson where we're going to talk more about 92 00:05:54,940 --> 00:05:56,290 mathematical operators 93 00:05:56,560 --> 00:06:01,540 like the plus sign and others that you can use in your code. So for all of that 94 00:06:01,660 --> 00:06:03,490 and more, I'll see you on the next lesson. 8916