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>> SPEAKER: Recall that in C, all data
types have a particular size.

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But that size may very well vary based
on the computer on which you're using

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C. Now, we happen to be using C inside
of the CS50 appliance, so inside of

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the appliance, how big is a char?

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How big is a double?

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How big is an int?

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How big is a float?

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>> Well, let's take a look
with some code.

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Include standard io.h, int main void.

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And now let's begin to declare
a few variables whose

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sizes we'll then print--

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char c, double d, float f, and int i.

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Now, I'm not going to store any values
in these variables, because I only

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care about their particular size.

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>> To see their size, I'll use print f,
as well as a C operator called size

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of, which will answer exactly
that question.

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Let's take a look.

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Print f char, followed by a colon,
percent 1, backslash n.

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In other words, I want to print out
char colon, followed by its size.

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>> So I'll include a comma
followed by size of c.

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Let's now do this again for a double.

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Print f, double, percent i, backslash
n, close quote, comma, size of d.

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Now notice, I'm going to continue using
percent i, thereby signifying an

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int, because what isn't changing is the
units in which I'm measuring the

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size of these variables.

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>> In fact, size of is going to return some
number of bytes, maybe one, maybe

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two, maybe more.

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But in each case, it will
indeed give me an int.

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And so that's the place holder I want
to use, irrespective of the type,

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whose size I'm getting.

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Let's do two more print f's.

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>> Float, percent i, backslash
n, size of f.

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Print f, int, percent i,
backslash n, size of i.

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

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Make, size of, dot slash, size of, and
we see that in the CS50 appliance, a

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char is one byte, a double is eight
bytes, a float is 4 bytes, and an int

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is four bytes, as well.

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