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# Using Numbers

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## Creating Random Numbers

The last function you’ll learn about in this chapter is mt_rand(), a random-number generator. All it does is output a random number:

```\$n = mt_rand(); // 31
\$n = mt_rand(); // 87```

The mt_rand() function can also take minimum and maximum parameters, if you prefer to limit the generated number to a specific range:

`\$n = mt_rand(0, 10);`

These values are inclusive, so in this case 0 and 10 are feasible returned values.

As an example of generating random numbers, let’s create a simple “Lucky Numbers” script.

To generate random numbers:

1. Begin a new document in your text editor or IDE, to be named random.php (Script 4.6):

```<!doctype html>
<html lang="en">
<meta charset="utf-8">
<title>Lucky Numbers</title>
<body>```

Script 4.6 The rand() function generates a random number.

```1   <!doctype html>
2   <html lang="en">
4      <meta charset="utf-8">
5      <title>Lucky Numbers</title>
7   <body>
8   <?php // Script 4.6 - random.php
9   /* This script generates 3 random
numbers. */
10
11  // Address error handling, if you want.
12
13  // Create three random numbers:
14  \$n1 = mt_and(1, 99);
15  \$n2 = mt_rand(1, 99);
16  \$n3 = mt_rand(1, 99);
17
18  // Print out the numbers:
19  print "<p>Your lucky numbers are:<br>
20  \$n1<br>
21  \$n2<br>
22  \$n3</p>";
23
24  ?>
25  </body>
26  </html>```
2. Include the PHP tag and address error management, if you need to:

`<?php // Script 4.6 - random.php`
3. Create three random numbers:

```\$n1 = mt_rand(1, 99);
\$n2 = mt_rand(1, 99);
\$n3 = mt_rand(1, 99);```

This script prints out a person’s lucky numbers, like those found on the back of a fortune cookie. These numbers are generated by calling the mt_rand() function three separate times and assigning each result to a different variable.

4. Print out the numbers:

```print "<p>Your lucky numbers
are:<br>
\$n1<br>
\$n2<br>
\$n3</p>";```

The print statement is fairly simple. The numbers are printed, each on its own line, by using the HTML break tag.

5. Close the PHP code and the HTML page:

```?>
</body>
</html>```
6. Save the file as random.php, place it in the proper directory for your PHP-enabled server, and test it in your browser . Refresh the page to see different numbers .