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>> DAVID MALAN: Let's write a program in
PHP that prompts the user for an

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integer and then determines
whether that integer is

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positive, 0, or negative.

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Here in conditions-1.php, I've already
gotten us started by opening and

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closing a PHP tag.

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Let's first declare a variable,
simply by doing $n.

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The dollar sign indicates that this is
a variable, and notice that we don't

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need to provide a data type.

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>> Let's now call a function called
readLine, which is similar in spirit

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to getString in the CS50 library for C.
But readLine also takes an argument

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that specifies the prompt that you'd
like to show to the user.

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For instance, I'd like
an integer please.

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>> Let's now analyze the user's input.

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If n is greater than 0, then let's print
out with printf, you picked a

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positive number.

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else if n equals 0, then let's print
out with printf, you picked 0.

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And lastly, else if the number is
presumably negative, let's print out

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with printf, you picked
a negative number.

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>> Let's now save this file and pass it
through to the PHP interpreter--

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php conditions-1.php.

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I'd like an integer please.

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How about 50?

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A positive number.

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>> Let's run it again with, say, 0.

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I picked 0.

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Let's run it again with,
say, negative 50.

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And I indeed picked a negative number.

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But notice, most importantly, just
how similar this syntax is to C.

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