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Will come back again in this list then we actually have an exercise exercise is this I'm going to set

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the stage for you.

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So you have two pieces of strings and I want you to find a way to attach them to each other I'm putting

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them together.

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That's essentially called apprehending or concatenating two pieces of things to each other.

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So let me go to exclude him.

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I'm going to start a new project say new project and this new project come on by and or is called the

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strings and in my hand the strings.

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And this is the staging part of the I'm going to do for you is going to be like this is going to be

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one of those is going to be a string string one that says hello and it's going to be a string ring true

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that says War.

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So then once you do is this I want you to find a way that when you print this if you print the two of

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them together so it says something like Hello world.

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I put the little space between them.

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So good luck and post the video here.

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Try it on your own.

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And then I'm going to go through that and I'm going to do it in multiple different ways.

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So we get a sense of so many different you know things in OK.

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I hope you succeeded and here's how I'm going to do it.

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I'm going to do it in several different ways.

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One of them would be the simplest one with Beatty's and Aslaug and then a slowdown would say there is

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one object there is on space between them.

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And then there is another object and then I'm going to say the string one on the string too.

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So essentially says preens what ever you'll find in this one with a little less space between them and

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then whatever you find in the other one that's printed out and see if it works.

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And now we have done hello or two separate ones.

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There's a space between them.

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This isn't however as funky as the next one.

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The next one is going to be like this.

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I'm going to say this thing let's call this one result of a string.

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This is the resist thing which is going to be a string string.

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Format in this thing with format I'm going to say essentially the same thing.

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I have one piece in space and I have another piece and the two pieces are a string one on the string

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two.

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So now I have a new string which is called resolve the string.

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The result the string is the result of being.

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This one is space and the next one.

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And of course I can now print that one.

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So I'm going to say and Aslaug what ever you'll find in resolve the string.

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So bring this here.

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Let's say this is first my third.

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This one is second method.

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Thank you.

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So let's do that.

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So we be expected.

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The boss are of printing the same thing.

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I could actually play a little cheating here and say first method is that and then say second method

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is out of place in the wrong place.

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After all the quotation marks of course.

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And now if you play or if you run the harp It says first method says your second mother says hello world.

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Now let's see another way of doing the exact same thing on this one I'm going to call her method and

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my method here's what I'm going to do.

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I'm going to say this thing or let's call it here.

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RAZ This ring her resolve this thing gets going to be my dream girl.

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One myth is read by appending a string and what do what happens with what happens with a string.

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So at the second string to the first string.

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Once again there is a string which is the result of appending the string to string one.

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And I should add a semicolon in my den in here let's print this one.

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Let's see if this one actually works on their method is Taro's resolve the string.

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What do you think is going to happen when I hit the wrong button.

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Let's see together.

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Yes Ron.

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And it does print but it doesn't have the little space to expected it.

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So here's what we could do.

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I could say first get the string one and append this through in a space.

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So by now here the result the string should be saying hello and a space then I'm going to say hello

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resolve the string is a tear.

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Resolve to string the string by appending the string to.

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So they get added to each other.

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Now this is a very important concept.

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Let's see the result and then I will explain it in a second so it prints it properly the way we want

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it.

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And now let me talk about that thing that I said.

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It's very important here.

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Result.

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The string is here.

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The result the string which is something that's easier and a simpler example of it in my hand is three.

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And then I'm going to say my hand is my in plus five.

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What does that mean.

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Is it if you show this through your high school teacher they would freak out because they would tell

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you.

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How can one side of an equation be the same thing plus something else.

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But that's the thing in programming.

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This isn't really a sign of equality.

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Rather it is a sign of assignments not the quality but the assignments.

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It means take whatever is on the right side of the assignments.

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Do the math on it.

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Do whatever you want to do to it and then assign it to the left side.

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So in this case it will be three plus five.

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That is AIDS and 8 cause might it becomes a mistake here there isn't this thing becomes what ever is

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in here.

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Resolve the string of pens to eat something else and then put it back in the territories or this string.

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Now if you're wondering what is the practical example of such a thing.

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Let me give you an example.

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Remember we had an integer play.

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Our turn of play or play or something like the effect that was essentially how many times player had

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played a round of play round of play let's say round of play is 0 and then player plays once then we

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say around of play these round of play plus 1.

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So it gets added to it.

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Let's say now the player has played.

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I don't know.

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Sixty five times and then it says round of play is 65 plus 1.

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So round of play becomes 66.

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So it keeps counting up walks towards whatever it is that you're trying to do.

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So this is a very common practice.

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Another common practice that's just of the building blocks of doing programming.

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It is essentially called assignment.

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Everywhere that you see an equal sign it's a sign of assignment.

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It doesn't mean that the side is equal to that side.

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It means the left side should become what is on the right side the left side should become what is on

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the right side of the equation.

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So that's about that.

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Before I finished this lesson I want to introduce you to an new concept as well.

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And that's the concept of mutable values.

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You see so far we had a string.

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But now I want to show you something called an as mutable string.

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And the difference between an and assisting an end is mutable a thing is that anything that is mutable.

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It means it can be modified so you can essentially say mutable means means more before any of that.

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So I know that we could actually take a string and put a value in it and then assign something else

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to it.

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For instance up here we could say a string one is low and then again we could say this thing 1 is not

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hello.

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What we couldn't do is go with this a specific characters and change them.

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You couldn't say whatever is the value in this thing.

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Go and find the one that says and modify that.

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And that is what we can do with immutable strings with mutable things.

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We can modify whatever is currently in them.

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So let's go ahead and make a new one.

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And it's interesting my mutable string.

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I'm going to give it a value such as my name for instance keep in mind that this is a wrong way of defining

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immutable strings because mutable things can not by default become strings and that's why it's giving

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me a warning.

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The correct way of doing this is this instead of that I'm going to have to write in as mutable a string

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as to with a string.

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So it's thought with a string based on a string of characters and what are those characters.

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It's essentially going to be mining.

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Or if you want in our case it could be a strange one.

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So I'm making immutable a string based on a string one.

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And then I could do things such as this I would say my immutable string.

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Append a string.

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What do I want out then.

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I want to append the space.

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And then I would say my mutable string.

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Append a string.

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Then what happened to it when I opened the string two treats.

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So this is essentially modifying the existing one on like the last time that we actually had to assign

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the value entirely saying whatever is in your add to that little bit too.

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And that's essentially a concept of mutability in Objective-C see a lot more of this when we talk about

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the collections specifically when we talk about N.S. arrays and as mutable arrays but they just want

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you to get a sense of what it means for something to be mutable.

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Don't be don't be puzzled by the term if the term is difficult for you just consider it as modifiable.

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So if something is mutable it means it can be modified its contents can be modified as you can imagine

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if I call this one my fourth method fight going on I say and it's like for all your self-worth.

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I hope so.

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My immutable string.

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Let's run it.

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And down in meannesses forth metod also has become Hello world.

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So that's about that.

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Let me zoom into it in a way that if you want to spend some time on it I can pause the video here for

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a few seconds and you can pause based on that once you're good with this.

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Let's move on to our next list.

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And there we use some of these learnings into using it using an actual iOS application.

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So I'll see you there.