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Hello will come again in this lesson you will be talking about four loops for loops are essentially

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a way for us to repeat a certain task a certain number of times.

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So if you want to do something 10 times or 20 times 100 times we use four loops for it.

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And that helps us with a variety of situations.

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Imagine if you're you know downloading the user from the backend and then our user has either 25 pictures

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and you want to do this thing 25 times or any similar situation.

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You will soon see that in every program that you write and every app that you write you use hundreds

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of wardrobe simply because that scene or that's hard as as often as they are used.

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They're very similar to if else statements are part of the control flow that let us do something and

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then based on a condition they continue or they stop.

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So just go ahead and see that in practice I'm going to jump into ex-cult.

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I'm going to close the previous project I'm going to say is one is for loops.

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Command line commands to

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and they're essentially to put together a method for writing a four to one type of loop.

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It runs based on a certain number of bytes ration.

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So you say run it for 10 times or 20 times the other type tells you to run for based on the number of

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elements in an array or a string or a number of elements inside a dictionary.

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So on and so forth.

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So let's see both of them.

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The first one I'm going to say for ends by is 0 until a smaller than 10 plus plus run the ATI and then

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every time I'm going to say it's like print Hello.

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Let's first see how what the result it produces.

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And then I'm going explain how it works.

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So if this Opterons or this project runs now we should be able to see Hello hello hello hello hello

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hello hello.

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Ten times versing Hello.

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So the way it's working is it saying there is a condition or must be below 10 and they're saying well

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what does the I start from it says I ask thoughts from zero.

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If it starts from zero is zero below 10.

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Yes let's go and do this and then it says now add 1 to our.

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So I becomes the one is the one below 10.

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Yes it is.

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Does this one keeps going on and on and on until let's say he is 8 and is saying is 8 is still below

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10.

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Yes it is then run this one says at one to it becomes nine the smaller And then this happens then nine

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adds one to itself it becomes 10 is 10 below 10.

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No it is not.

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So this is not going to happen anymore more and we end up in this next line of whatever it is.

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So this follow loop essentially happens and goes through all of its hydration until we get here.

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Now what if I want to print from either or 25 to 80 I could say and Aslaug what whatever you find integer

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type in itself thats an integer right.

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So is going to print 25 to 79 like the other relational operators if you want to include 80 you could

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just say until it is smaller or equal to 80.

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So if you have an equal sign in there now 80 is going to be included in our in our iteration as a starting

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gain from zero or two.

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Let's say 10 and now this is going to happen 11 times.

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I just want to say whatever that you are trying to do in here for 11 times which in this case is just

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printing the eye.

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You should also remember that it is again arbitrary.

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You can name it whatever you like.

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The same may in and then that becomes and as well.

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And then this becomes an.

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So we think that gain or we run again because I see the same thing a lot of times people actually call

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these counters.

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So between counter zero counters more than 10 counter plus plus Prange counter for the kind of game

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we see the same result.

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Now let me revert back to you which is a more common way of writing it.

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I want to explain another thing for you.

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This thing in here if you remember from one of the previous lessons this is incrementing I buy one.

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So is going 0 1 2 3 until it is a smaller or equal 10 and then it gets to 11.

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This fall finishes what people want it to go.

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Every other one whatever if want it to go on lead to even numbers I would say plus equal to.

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So instead of just adding 1 I would say I'd go to the to treat a treats for increments to every time.

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Let's see that it should print 0 2 4 6 8 10.

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Just like what we expected.

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So that's another way.

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Another thing to keep in mind that the patient doesn't have to go.

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One other time even though most likely that is what you want and that's what we usually do.

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You go 0 1 2 3 4.

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We go in or there.

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You could if you wanted to jump every turn to 1 or be 51.

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If that's something that that you might need.

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Now with that in mind let's move on to another type of 42.

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So this what we call it a four new merge.

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And now let's go ahead and do 4 in that see four in the works.

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I think we saw something like this in one of our previous lessons because we needed to.

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Yes.

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When we were doing sets we saw that but let's see them once again and ask are they going to call this

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one my array is on and this are a lock.

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And in it with objects and the objects are let's say Wednesday and then there's another irrelevant object

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called Max.

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And then there is another object called by us.

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And then there's another object called Friday and there's so many random objects that they seemingly

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don't have any correlation with each other.

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They don't have to have it inside the pause at the end.

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We have a name that says this is the end of my Airey and I forgot the one bracket in here.

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Like I said it's a very good practice if you stack them like this.

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So you actually can see them quite clearly.

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So what if I want it to go to the objects in this array.

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So let's write that I'm going to say for instance is zero.

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And these are.

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It is a smaller.

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So what should be a smaller from let's say in my array there is 1 2 3 4 5.

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So I could see a smaller than five which obviously means zero.

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One two three and four.

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That's one way of doing it.

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The other one would be my array doth count.

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So it always depends on my array of course.

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All right.

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Plus plus increments.

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And then you might incrementation in my area I'm going in my for loop I'm going to say and like are.

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This is for instance or whatever you find.

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What is it that we're looking for.

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Why are they not like that.

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I've checked that index.

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I let me clear this one.

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Or let me just comment it out and then I'll explain this once again.

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Let me see what we get.

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So this is Wednesday math Iowas Friday and Saturday so it's saying go between zero and the count of

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the aere increment one at the time each time.

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Print this part and whatever you find and then go to my array find the object that that index.

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So if I 0 my array 0 if I use one my array one is eyes to my array to so on and so forth.

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So this goes through the array and finds all of the objects.

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However I told you I'm going to show you another way for doing it not in numeric for loop which you're

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again doing in here so that other wave would be like this.

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I'm going to say for NSA string any for each or whatever you want to call it in my.

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It's means go to my array for objects of the type in the string go through them.

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One other time and then place each of them as each call each of them each.

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Or let's say in so it says go through my array.

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One other time.

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Call them and me.

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And then what do you want to do with it.

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I want to say and it's like whatever you find in any.

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So it's saying go through the array one item at a time.

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As long as there is a string one item at the time call them any so.

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Annie.

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Annie.

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Annie.

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ANNIE.

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And any.

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And then preinstall.

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Let's see what we get if we do that.

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If I run this application now we shouldn't get Wednesday Mantz I was Friday on Saturday exactly the

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way that they are in here.

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So that's about that.

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A quick recap.

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We do four loops and we want to repeat something a certain number of times we start from summer and

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summer.

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Remember what we want to include.

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The last one or the one in the last one.

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We can increment with different ways incrementing one other time when you're printing several other

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time and you could use for in loops we could use it for a certain type of object in whatever object

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we're looking for and then print the values that we want or do whatever we want to do with those values.

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One of the things that we for instance we could do in here is we could say for any object in my array

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Let's see if there is a Monday.

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So I'm going to say for any in my array if any is equal to a string of Monday Monday.

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If that is the case then and Aslaug Monday is there.

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So if you're searching for a certain item you could do it like this and say go through this if it is

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there printed.

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Obviously Monday is not there now and he's not going to print it.

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But if I was searching for oils anyway withdrawn this would say for any of them.

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Yes.

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Was is so perfect with the money.

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Let's move on to our next lesson.