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So why do we need Loop's, because there are many cases when you have to do the same things again and

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again and again, when I think of Loop's Bart Simpson comes to my mind when he is punished to write

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a sentence on the blackboard a hundred times in code, it could be done by copy paste in the same line

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a hundred times.

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But I think most of us would miscounting after 30.

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But it can be done much easier with loops.

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What are loops?

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Loops are repeating code until a specific condition is met.

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In the case of Bart Simpson, the specific condition is reaching a hundred.

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Now let's see what we are going to cover in this lecture.

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There are a few loop types in Java.

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First, we will look into why then do y loop after those for loop.

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And finally, I will tell you what and how continue and Brachy words can be used.

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The next lecture will be a coding lecture and I will give you examples to all of these.

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First, let's look into while loop.

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It starts with while then a condition in parentheses and the code that will be executed repeatedly is

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in curly braces.

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Java will keep continue executing the code until the condition is true.

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I think an example make it more clear.

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Right.

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So we have to print out being right.

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Sock's a hundred times.

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So first we have to define a variable for the loop strictly outside of it.

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We will call it AI and its value will be one then the wire loop with a condition that it should be less

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than or equal to a hundred.

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And the code in the curly braces.

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After we print out the text, we increase the value of AI by one.

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After the value of AI is increased, we get back to while and Java checks, whatever.

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The condition is still true.

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If it's true, it can continue executing the code inside the curly braces.

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When the condition is false, it continue executing the code after the loop.

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It's really important to keep in mind that the value of I must be modified in the loop.

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If you don't modify it, the condition will remain true and the code will never stop and we get into

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an infinite loop.

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Later, we will use the loops for more complex code than just printing out something.

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So now let's move on to do while it's form a bit different from while first do word, then the curly

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braces with the code and then the wire keyword with the condition and last a semicolon.

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Now, let's see an example we used in case of while transformed into a do.

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While the biggest difference between a while and dubal is that while checking the condition before it

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starts running it and if it's true, it will start executing the code.

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If it's false, then it will skip the code in the curly braces do while runs the code first without

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any checks and tests after the first code execution is finished.

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So the code will be executed at least once after the conditioned check is finished.

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The execution starts again from the beginning of the do while loop.

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It's also important to keep an eye on the value of AI and don't let the condition be true all the time.

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Moving on to for loop the form of the for loop is the following.

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First for key keyword parentheses, then initialization, then semicolon.

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Next is a condition, then a semicolon and an updated statement and lost the code in the curly braces.

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Let's take our example we used before.

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For Int equals one semicolon, I must be lesser or equal to a hundred than semicolon and I plus.

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Plus and the code.

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The big advantage here is that we don't have to create a variable outside of the loop and we don't need

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to increase the value of AI in the loop.

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So for Loop is much cleaner because we can do all the administration in one line and it is the best

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choice if we know how many iterations we have to do after the code is finished, we get back to the

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first line of the for loop.

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First, it increases the value of AI and then checks the condition.

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If it's true, it keeps running the loop.

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If it's false, then it will stop the execution of the loop.

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An extra thing here we can put a loop into another loop in case of our example code.

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The text will be displayed a thousand times.

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First, the inner loop will be executed and the text will be printed out ten times.

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The value of I will be increased to and the inner loops code will be executed ten times again.

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And it goes on and on and on.

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You can also do this with while or do while.

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Now the two key words before the coding part.

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First one is to continue keyword.

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It is actually for skipping steps and loops in our example.

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If you use if I know I haven't talked about it, but I think you can imagine what it does.

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So the loop goes on and when the value of AI is ten, we skip the tenth print statement, but the loops

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execution goes along and at the end ninety nine lines will be printed instead of one hundred because

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we skipped at the tenth.

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The next one is break.

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Break is for different purpose.

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It stops the loop.

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We use the same code, but I change the continue to break.

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So after printing the text nine times the loop will be stopped.

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Break and continue are not used very commonly, but there are cases where they are very handy.

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That's it.

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Let's continue with the coding part.