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SPEAKER 1:Let's write a program that
gets an integer from the user, without

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using the CS50 libraries
function, get int.

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To do this, we're going to use
a new function called scan f.

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That it turns out, get int in the cs50
library users underneath the hood.

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Here we go.

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>> Let's first declared an int.

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Let's call it arbitrarily x.

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That will ultimately put
the user's integer in.

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Let's now prompt the user for that
number, as with number, please.

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And now let's call scan f, as follows.

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Scan f, quote unquote percent i,
indicating that what I want to get

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from the user is indeed an integer.

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But now I need to provide storage
space for that integer.

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I can't just pass in x, because recall
that when you pass an argument to a

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function, it's typically
passed by value.

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That is a copy is passed in.

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So instead, I want to provide scan f
with the address of x so that it can

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actually change the value
at that address.

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To achieve that, I simply need to pass
in ampersand x in order to pass in the

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address of x.

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>> Lastly let's go ahead and print
out for the user exactly

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what he or she typed.

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With print t, quote unquote, thanks
for the-- percent i is our

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placeholder, followed by x this
time, not ampersand x.

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Because, as always, I want to pass into
print f exactly the value that I

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want printed.

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>> Let's now save, compile,
and run this program.

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Make, scan f zero, dot slash,
scan f zero, number please.

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Let's provide it with o 50.

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And thanks for the 50.

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