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In this video, we'll do a
quick overview of looping in

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general and specifically in c++.

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Looping is also called
iteration or repetition.

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It's the third basic building
block of programming.

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After this section of the course,
you'll have all you need to begin to

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solve very complex problems, using
sequence, selection and iteration.

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In this course, we're covering c++.

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However, all programming
languages must support sequence,

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selection and iteration.

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Once you understand these concepts
completely, then it's just a matter

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of picking up the syntax of another
programming language and you'll

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be able to implement solutions to
problems in those languages as well.

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Loops allow the execution
of a statement or block

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of statements repeatedly.

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And they're made up of two sections.

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First, the loop condition
which determines when we

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iterate and when we don't.

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Second is the loop body.

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That's the statement or block of
statements that will be repeated.

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That's it.

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Conceptually, it's very simple.

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Let's look at a few
use cases for looping.

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Here are some typical
use cases for looping.

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We want to execute a loop or repeat
statements a specific number of times.

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For example, we want to do something
10 times or we ask the user how many

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times they wish to do something.

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Another use case is iterating one
time for each element in a collection.

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So suppose we have items in an
array or a vector, and we want

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to process each of those items.

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Other times we want to loop until
a specific condition becomes true.

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So we loop until we see a
specific value then we stop.

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Of course, we can also loop forever.

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This isn't as common as the other
use cases, but operating systems

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are an example of programs that loop
forever executing system processes.

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There are many other use
cases and variations of

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these existing use cases.

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Let's look at the c++
looping constructs now.

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C++ has three main looping
structures: the for loop, the

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while loop and the do while loop.

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The for loop has a ranged base
variant, which is really great.

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First, let's talk about the for loop.

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The for loop is typically
used when you want to iterate

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a specific number of times.

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For example you want to loop
10 times or end times, where n

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is determined by the program.

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The range-based for loop makes
it really easy to iterate through

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a range of items or through
the elements of a collection.

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With arrays vectors and
other collections, this

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is a great loop to use.

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The while loop iterates while a
specific condition remains true.

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When the condition becomes
false, we terminate the loop.

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In the case of the while loop,
the condition is checked at the

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beginning of every iteration.

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The do while loop is similar to the
while loop, except that the condition

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is checked after each iteration.

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With only these basic
loops, we can implement any

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iteration pattern we want.

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All programming languages
have loop constructs.

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The c++ loops are clear and concise.

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Let's go through the
c++ loops one at a time.

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Let's start with the for
loop in the next video.