1 1 00:00:00,930 --> 00:00:02,500 Hi guys and welcome back. 2 2 00:00:02,500 --> 00:00:05,390 In this video we're going to building our first app. 3 3 00:00:05,390 --> 00:00:07,030 Think of it as a bit of a recap 4 4 00:00:07,030 --> 00:00:09,450 of everything we've learned so far. 5 5 00:00:09,450 --> 00:00:12,380 The app we're going to build will ask the users 6 6 00:00:12,380 --> 00:00:14,840 for their age, and then it will tell them 7 7 00:00:14,840 --> 00:00:17,230 how many months that age equals to. 8 8 00:00:17,230 --> 00:00:22,230 So for example, if they enter 10, the app will say 120 9 9 00:00:22,250 --> 00:00:25,420 because that's 12 months in each year of course. 10 10 00:00:25,420 --> 00:00:29,410 And so let's get start by asking the user for their age, 11 11 00:00:29,410 --> 00:00:32,340 and we will say for example, user underscore age, 12 12 00:00:32,340 --> 00:00:34,700 and then we're gonna use the input function 13 13 00:00:34,700 --> 00:00:39,233 to get the user's age, we'll say input Enter your age. 14 14 00:00:40,440 --> 00:00:43,450 Then remember that this is going to give you back a string, 15 15 00:00:43,450 --> 00:00:46,300 so we need to turn it into an integer or whole number 16 16 00:00:46,300 --> 00:00:48,470 so that we can do maths on it. 17 17 00:00:48,470 --> 00:00:53,203 So we will say something like years equal int of user age. 18 18 00:00:54,270 --> 00:00:57,120 Now we're gonna calculate the months that that equals to 19 19 00:00:57,120 --> 00:00:59,480 so that we can tell the user that information. 20 20 00:00:59,480 --> 00:01:03,103 So we'll say months equal years times 12. 21 21 00:01:04,010 --> 00:01:07,120 Finally, we're gonna print it out for the user to see. 22 22 00:01:07,120 --> 00:01:09,310 So you could do just print months, 23 23 00:01:09,310 --> 00:01:10,970 but that's not gonna tell the user a lot 24 24 00:01:10,970 --> 00:01:13,650 about what it actually means, this variable, 25 25 00:01:13,650 --> 00:01:15,470 unless they know what the programme does, 26 26 00:01:15,470 --> 00:01:17,100 it's not gonna be all that helpful. 27 27 00:01:17,100 --> 00:01:19,570 So instead, I recommend using an f string 28 28 00:01:19,570 --> 00:01:23,090 to print the information in a bit of a readable format. 29 29 00:01:23,090 --> 00:01:27,020 So we can say something like Your age, years, 30 30 00:01:27,020 --> 00:01:30,293 is equal to this many months. 31 31 00:01:32,070 --> 00:01:35,530 So if we run this file, then you get asked to enter your age 32 32 00:01:35,530 --> 00:01:37,810 let's say 30, and then you get, 33 33 00:01:37,810 --> 00:01:41,870 Your age, 30, is equal to 360 months. 34 34 00:01:41,870 --> 00:01:44,340 So this is our very first application 35 35 00:01:44,340 --> 00:01:47,020 that actually does something, and you can extend this 36 36 00:01:47,020 --> 00:01:49,220 further and I would encourage you to do so, 37 37 00:01:49,220 --> 00:01:50,790 just to play around with the code, 38 38 00:01:50,790 --> 00:01:54,070 and so that instead of printing out the number of months, 39 39 00:01:54,070 --> 00:01:55,930 you can print out the number of seconds 40 40 00:01:55,930 --> 00:01:57,360 that this is equal to. 41 41 00:01:57,360 --> 00:01:58,980 Of course the maths is gonna be slightly different, 42 42 00:01:58,980 --> 00:02:00,980 you're gonna have to multiply a few more things here 43 43 00:02:00,980 --> 00:02:02,840 to calculate the number of seconds, 44 44 00:02:02,840 --> 00:02:05,040 but that should let you play around 45 45 00:02:05,040 --> 00:02:06,400 with this code a little bit. 46 46 00:02:06,400 --> 00:02:08,490 Something else that you may wanna think about, 47 47 00:02:08,490 --> 00:02:10,880 is simplifying this code a little bit, 48 48 00:02:10,880 --> 00:02:13,120 'cause at the moment we've got our input 49 49 00:02:13,120 --> 00:02:16,330 and then we have this variable called user age, 50 50 00:02:16,330 --> 00:02:19,270 the user age variable is only used 51 51 00:02:19,270 --> 00:02:22,500 to be converted into an integer in the very next line. 52 52 00:02:22,500 --> 00:02:25,460 So actually, we could just put the int function 53 53 00:02:25,460 --> 00:02:30,130 around that input, so now what we're turning into an integer 54 54 00:02:30,130 --> 00:02:33,960 is the result of calling the input function 55 55 00:02:33,960 --> 00:02:35,690 which is gonna give us the string. 56 56 00:02:35,690 --> 00:02:39,750 So the value the user enters will be this, 57 57 00:02:39,750 --> 00:02:42,160 and then that will be turned into an integer. 58 58 00:02:42,160 --> 00:02:45,920 So we actually don't need this line at all, 59 59 00:02:45,920 --> 00:02:48,930 although we do need to use the user age 60 60 00:02:48,930 --> 00:02:51,090 instead of the years variable. 61 61 00:02:51,090 --> 00:02:52,760 And that is a little bit simpler, 62 62 00:02:52,760 --> 00:02:54,620 and the reason for doing that is, 63 63 00:02:54,620 --> 00:02:56,080 so that you don't have a variable 64 64 00:02:56,080 --> 00:02:58,520 that is only used as a temporary measure 65 65 00:02:58,520 --> 00:03:00,720 before it gets converted into another type, 66 66 00:03:00,720 --> 00:03:03,120 so you can put functions inside of functions 67 67 00:03:03,120 --> 00:03:04,400 when it makes sense, it can make your code 68 68 00:03:04,400 --> 00:03:07,130 a little bit less readable, but in this case, 69 69 00:03:07,130 --> 00:03:09,440 I think it's OK, it is simple enough 70 70 00:03:09,440 --> 00:03:11,890 that it should make a lot of sense. 71 71 00:03:11,890 --> 00:03:14,370 That's it for this video, do tackle the extension 72 72 00:03:14,370 --> 00:03:16,300 which is to print out the number of seconds 73 73 00:03:16,300 --> 00:03:18,900 instead of months, and I'll see you in the next one.