 Okay, so that program was nice, but what if I want, you know, maybe some interaction? I want to have the user start to work with me. One of the things we can do is we can start to use the same kind of approaches that we saw with print, and one of the functions that we happen to have at our disposal is this idea called input. Now, the same kind of approaches are actually coming in. You might remember from your math class all of a sudden, you had a symbol like this. And that's a crude F, but we had F of X, function of X. The entire concept there is that this F, well, that's just my function's name, and this X, this is just my parameter. Whatever I put in here, I'm expecting F to do something too. Now, input, well, print, actually, we'll think about print, print took a string in, and it said, well, whatever took that parameter, and it did something to it. What did it do? It displayed it on our string. Input is going to do sort of the same approach. Let's say, let's say, for example, I know, let's say I want to do the exact same kind of approach. I want to do input. Well, all right, let's say length equals input, enter a length. Now, you notice I did add a little kind of space there. That's just more of a stylistic thing in my opinion, because when I hit enter, now I've got one extra space, it just looks better in my opinion. And so all of a sudden, I can type in whatever I want. But if I say hit enter, and then type out length, I see that I get the 100, awesome, excellent. So let's do this again with a few of our other variables that we wanted to work with. Now I'm going to cheat a little bit. I'm going to come up to length, I'm going to hit enter. Now I'm doing stuff with my hands. I know you guys can't see the keyboard, but I'm going to hit, and there you go, I'm going to hit the home key, I'm going to hit delete a few times, and I'm going to type in width. Now I'm not going to hit enter, because you notice in our length, that's not what I want. I'm just kind of coming in and actually reusing what I've already typed in. I can hit enter, enter a width, we'll say 45. And so this time without the keyboard, we can do the exact same thing for my height. So I come in, I take that, delete width over here, hit end to kind of speed through that, highlighting this, I'm holding down the shift key as I do this. Height, if you wanted to, you can still use your mouse. I can clearly use that stuff here as well. Enter a height, all right, well, 25. Okay, well, we already know kind of how we do the area. It was area equals to asterisk. Remember we had to do that asterisk. And I like to kind of fill this in, because we're going to be typing out a lot of stuff, so I go parentheses, plus parentheses, plus parentheses. Now I'm just spacing things out to have a little bit better visibility, because now I take my three variables that I've just created, length, width, and height, and I'm pretty much multiplying them all together in sort of a round robin. So width times length, and I'll come over here and it'll do width times height, and so now width is handled both of them, and so the only one that's left is taking length and height and multiplying them together, so length, length, and height. Why am I getting an error? Well, let's actually kind of look at this from another perspective for a second. You see that in my slides I've got input, and I talked about that idea of a function. We also have something called print. Well we have other functions as well, and one of them that we have is something called type. And whatever I put inside of type, it's going to basically spit out sort of what type that is. So I'll leave, I've still got that code, I've still got all that stuff. If I've said something like type 5, well type 5 gives me this int, it's telling me it's an integer. If I did type 3.14 for pi, this is going to tell me it's a float because I have decimal points. Well, okay, alright, so let's see what our variables are. Type width, str, it's a string. You see, when we type something in inside of input, Python interprets all of it as just string input. And this is throwback to back when they try to interpret for us that kind of became a vulnerability in kind of Python. So instead they said screw it, we're just going to handle everything as if it was a string. So I need to be able to convert, okay, so how do I convert? Same kind of approach we've been doing the entire time. I have these different functions, I've got an input function, I've got a type function, I've got a print function. I also, if I want to do conversions, have the ability to use something like int, parentheses and put something in here, float, parentheses, put something in here, and I can even actually do an str, put something in here. And if you kind of notice, those are exactly the same things that we're seeing with type. Let's actually kind of see that in action. If I type int, you notice it kind of becomes a dark purple. Oh, and it's even kind of giving me a little hint, you know, if you, whatever you put in here, it's going to turn into an integer. So let's say, for example, let's put in width for this. Okay, well, width we just learned was a string. Just now all of a sudden it's saying it's a, well, we're just seeing that kind of 45. So what I'm going to do is I'm going to do a little bit of left to right association here. I'm going to say width. Remember, the left side of sort of my expression is my memory address, where in memory should you be saved? And then I'm going to come over onto the right side of the equation. This is the expression. This gets evaluated out first, gets evaluated out first. So if I come in here and say int width, width is all of a sudden going to be taken and changed from a string into an integer and then saved back into its original spot. So I hit enter. Okay, prove it. Well, it can come up here. I can take the same width type or type width formula that I have been using. I can hit enter and it brings it automatically down to the bottom. And if I hit enter, I can see that all of a sudden width is an integer. Well, if this is the case and what I can do is I can sort of speed through this the same way. I can click on width equals int width, change this from width to length, change this one as well to length. All right, all right. Just to test that out again, length, we see that it's also in it. And then finally, we do one last one with height, height, height, I can hit enter. And now, again, I've already got that mathematical formula. Even though it's off the screen, I know it's up here. I can kind of come up to it. I can come back, hit enter, all right. In theory, all of this should work, right? Oh, it did. And if we kind of come in, just because we've been dealing with all these different functions, print area, ah, 16,250.