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Hello, everyone.

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Today, we will continue our best scripting videos with while use a while loop in any programming language

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is to repeat the same line or a set of lines over and over until you meet a certain condition.

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Let's take an example.

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In this script, we're creating a variable eye and assigning it a value of zero.

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Then we build a while loop by checking if I is less than or equal 10.

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If it's not, then echo this line.

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But it's very important to keep in mind that if we close our script like this, it will run forever

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because I will be zero forever, right?

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So basically I will be less than 10 and it will never become 11 for the loop to stop.

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So let's change the value of AI inside our.

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Noice.

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We can also have an infinite while loop without any condition to stop it, but then we have to specify

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our own condition inside the loop in order to stop it.

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Let's take an example.

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In this example, we're creating an infinite while loop just by adding colon after the word while here.

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Then we will keep reading a number from the user and tell the number we're reading is bigger than hundred.

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If that's the case, then we break our law by using the word break.

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Let's try it out in action.

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Nice, as you noticed, our look only stopped when we entered hundred and one, which is greater than

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a hundred.

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A very useful example of using one is to read data from a file.

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Let's take a look.

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First, we have a file here called Passwords.

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This file has two columns separated by space.

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We kind of did this before using OK, remember, let's do that now and said our best fit

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in this group we're using while loop to keep reading data and stored in a variable called line.

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Then we are assigning the output of this command here to user and the output of this command to pass.

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We explained this command before, but in general we are splitting each line into two fields, separated

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by space.

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Then we take the first column, which is No.

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One here for the username, and we do the same, but for column number two for the password.

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Then we split them again, using common here.

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Then we call the two variables in this line.

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Finally at the bottom, we're taking input from my file, which is defined at the top of the script

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is where?

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Let's run it now and see the apple.

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Perfect.

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Let's take another example and how to take input from the user and match that input against the data

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we are getting from the final.

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In this script, we ask the user for his username and his password, same way we did before, and we

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check if the username and password matched the ones we get from the file.

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If they do, then we echo, they match, and then we break the loop.

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Let's run it.

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Notice, the only user and password match was the user nudniks and the password, Iola Besch, let's

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verify that.

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Here.

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We have reached the end of this lesson, please practice and see you in the next one.