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Not let's look at a very commonly used Concord for a statement called for a statement or follow up.

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So it has something to do with looping a fun loop is typically used to iterate or loop over elements

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of an array or a similar data structure and do something with each element like printing what the element

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is.

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For example when we visit e-commerce websites Visi products displayed as a list.

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This is usually done with a follow up.

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That is the products would be stored in some kind of a data structure like an IRA under for a loop.

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What they don't want the array to display each part product stored in the art that is in each iteration

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data associated with one product is displayed.

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Let's see how a for loop accomplishes something like this.

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Follow up is basically an iteration statement.

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Need it you know it's our executive block of code for some number of things.

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How many times a block of code is executed is dependent on some condition.

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I think the best way to understand follow is to be a simple example.

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And here we have one here you have an idea containing an immense Indigos zero to nine under statement

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simply because there are elements so the statement includes the key word for followed by parenthesis

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which includes a few xperience that and this is followed by the body of follow up riches and President

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quali basis know within the band this is we have three expressions separated by semi-colons and these

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two semi-colons are mandatory the first expulsion is basically an initialization expression and it is

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initializing the variable to zero.

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I is basically used as a risk index number also since I is being declared here it is visible only within

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the first statement that is it is accessible outside of the for statement the second expression is a

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condition and it is what decides whether the body or for statement should be executed or not.

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So during the first iteration the condition would be zero less than 10 done is the size of the third

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expression is simply an increment operation which helps and it did it in the ADI So those are different

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expressions within the patent cases.

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Now let's look at the concurrent fruits and so initially in the first iteration the variable I would

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be initialized to zero.

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And then next up condition is checked that is whether I is less than 10 is true or false since I have

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zero and zero is less than 10.

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The body of first statement is executed.

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So the first element of the array gets printed.

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Next I will be incremented to one due to the increment expression end up a nation will be checked once

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again.

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Distend the condition will be run less than 10 which is also true.

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And so the body of false statement gets executed again and this time the first element of the array

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would be printed next I would be incremented to after it is a condition Bulla's then is ject.

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So the cycle of checking the condition excluding the body or first statement and then doing the increment

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operation continues until I become certain at which point the condition fails as done unless less intent

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would be false.

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So at this point the fun look for the exit under statement following the for loop would be exaggerated

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.

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So the initialization expression is executed only once.

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But the other two expressions on the body are for a loop are executed multiple times at the end of the

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lesson Wyburn exhibit the simple example and we will also try on some of the stuff that we are going

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to see in this lesson here is a general form of a statement like we discussed the parenthesis includes

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three parts initialization condition expression and the exhibitionist expressionless part is the part

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that usually does the increment or sometimes even decrement operation.

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Here in addition Parker can be either a variable declaration statement or it can be a list of common

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separated expression statements if you recall a statement can be of three types declaration expression

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or a control flow statement is the expression this part can also have a list of comma separated expressions

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statements but it cannot have any declarations statements condition expression will always be some kind

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of a boolean expression not just look at each of these parts up lately although for the sake of completeness

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we will look at several different ways in which four statements can be written.

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Typically you would not write for loops that are different from the example we saw earlier.

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So let's begin with the initialization part.

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The initialization part is optional.

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And the example we just saw can also be rewritten as shown here.

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Hear the index variable initialization is done outside of outlook on the initialization part of the

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for loop is empty.

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Initialization part can have a single declaration statement on this is the most common scenario.

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On Here are a few examples.

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First example is straightforward.

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On something we have already seen second example is declaring variables and we know that it is a valid

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declaration statement third and fourth examples are invalid third is invalid.

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Even the board wearables are same type so you can only have one declare Mission Statement in the initialization

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part.

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Note that these last two examples are invalid even if those statements appeared independently outside

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of a statement.

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So basically what we are seeing here are proper declarations statements and if they are invalid outside

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of her statement then they are invalid even when used within the first statement.

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Initialization but can also how a list of explicit statements that are called Must up later on let's

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look at few examples.

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Here in the first example the variables i and j are being re-initialize that is they're already declared

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outside of Outlook and they are simply being reinitialized here.

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Second example shows that you cannot mix an expression statement with their declaration statement next

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we can have all of these expressions statements and they are all valid.

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And I would say you should avoid using initialization part and this bit as I'm sure many birds are not

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even aware of such a possibility and hence the code would be very confusing.

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So use any or they can but for either variable declaration or variable re initialization next is condition

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exhibition on Binoy it must evaluate the boolean value it can also be optional.

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And so if omitted it Drew would be as you were and we may end up with an infinite loop.

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And here is an example.

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No one didn't find a group that can use a break statement like in the case of switch statement using

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break statements with followups will be discussed later.

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Find them if you have the experience part they can also have a list of call most x Mission Statements

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like in the case of initialization part.

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And here is one example which has been just rewritten here the print statement has been moved into the

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expressionless part which also includes the increment operation not the semicolon is required at the

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end of her statement as there is no explicit body we can also take this one step further and make it

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even more compact.

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Unheeded is here the inexplainable is incremented within the print statement itself.

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All we can write our statements.

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This meant Typically you would have only an increment or decrement operation in the expression of the

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spark.

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So that's a fair statement.

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No let's go ahead and Bouchard them all of some of the stuff we have learned in this lesson.

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In the interest of time I'm going to show this to mind my Eclipse ID.

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And here we are in the basic class within domain.

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And this is the same example that we have seen earlier where we are printing the elements from zero

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to nine.

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So let's just go ahead and run this.

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Just click this button here.

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And as you can see all the elements of getting printed here.

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OK.

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And so this is the most typical way in which you would use a follow up.

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OK.

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But we have also seen different reason which could be used different Boehmer additions and combinations

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.

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And you look at some off them so one of them was that the initialization part can be optional.

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So the declaration can be done outside of loop.

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So it should give us the same result and you can see that we have the same result here.

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So let me just move it back now we also said that we cannot have this kind of declaration.

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So it is invalid and it giving it completion.

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So you can see that red line here.

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So the right re is.

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So this is the right way off declaring it.

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OK.

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So this is still a declaration statement.

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Now we said that we can that initial edition but and also how ex-Special statements.

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So so this is a declaration.

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And here we can re-initialize them do i equal to one.

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And Jake will do one not this would only print the elements 1 2 9.

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OK.

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So we how IAG is not being used anywhere.

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So in this case you can see that it's printing 8:59 now other than that we also can how expression statements

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over here multiple exhibitions statements in the exhibition list and that's also put I lay off de Let's

128

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put an empty string here Mr. double caught quote then whitespace let me just make it g.

129

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So you also how I and J now.

130

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And let's also put another condition here.

131

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Get less than I read out and so that's the whole condition expression and we are incrementing both I

132

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and J here.

133

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So let's just run this.

134

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So now it's blending dot elements and this bit I read off by an idea off just so it will just be the

135

00:10:45,130  -->  00:10:46,750
same element.

136

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Now let's just go back let's make it I equals zero.

137

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Let me also remove this

138

00:11:02,820  -->  00:11:07,950
and if you recall the last example was moving this here

139

00:11:10,650  -->  00:11:15,470
and making this plus plus unlimited modus

140

00:11:19,980  -->  00:11:22,170
So the opening statement has been moved here.

141

00:11:22,300  -->  00:11:27,550
But as you can see it gives a compiler because there is nobody and said that we need a semicolon here

142

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.

143

00:11:28,060  -->  00:11:29,910
Now it's right.

144

00:11:29,920  -->  00:11:35,550
So this is the most compact form on if you add on it it prints all done in advance.

145

00:11:35,560  -->  00:11:37,640
So that was the last one which we have seen.

146

00:11:37,930  -->  00:11:39,910
So that's a lot for loop.

147

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And next we will look at something called and hands for loop and also in the seamless entry would also

148

00:11:46,420  -->  00:11:49,890
look at a commendation from effective July item.

149

00:11:49,930  -->  00:11:52,410
Ok then go ahead and try this out.

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Play with it and that's it.

151

00:11:54,760  -->  00:11:55,860
Happy coding ironed.

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Thank you