PHP

Implementation of programming language PHP

Standard implementation of PHP, written in C.

PHP Logo
PHP Logo

Links:

Examples:

Factorial:

Example for versions PHP 5.2.4, PHP 5.3.2

This example uses recursive factorial definition. 

<?php
function factorial($n)
{
    if ($n == 0) {
        return 1;
    }
        
    return $n * factorial($n - 1);
}

for ($n = 0; $n <= 16; $n++) {
    echo $n . "! = " . factorial($n) . "\n";
}
?>

Hello, World!:

Example for versions PHP 5.2.4, PHP 5.3.2 
<?php
echo "Hello, World!\n";
?>

Fibonacci numbers:

Example for versions PHP 5.2.4, PHP 5.3.2

This example uses recursive definition of Fibonacci numbers. 

<?php
function fibonacci($n)
{
    if ($n < 3) {
        return 1; 
    }
    
    return fibonacci($n-1) + fibonacci($n-2);    
}

for ($n = 1; $n <= 16; $n++) {
    echo fibonacci($n) . ", ";
}
echo "...\n";
?>

Quadratic equation:

Example for versions PHP 5.3.2 
<?php

echo "A = ";
$A = (float) fgets(STDIN);
if ($A == 0) {
  die("Not a quadratic equation\n");
}

echo "B = ";
$B = (float) fgets(STDIN);
echo "C = ";
$C = (float) fgets(STDIN);

$D = $B * $B - 4 * $A * $C;

if ($D == 0) {
  echo "x = ", -$B / 2.0 / $A, "\n";
  die();
}
if ($D > 0) {
  echo "x1 = ", (-$B + sqrt($D)) / 2.0 / $A, "\n";
  echo "x2 = ", (-$B - sqrt($D)) / 2.0 / $A, "\n";
} else {
  echo "x1 = (", -$B / 2.0 / $A, ", ", sqrt(-$D) / 2.0 / $A, ")\n";
  echo "x2 = (", -$B / 2.0 / $A, ", ", -sqrt(-$D) / 2.0 / $A, ")\n";
}

?>

CamelCase:

Example for versions PHP 5.3.2

This example uses string functions and regular expressions. Function ucwords converts first letter of each word to uppercase. 

<?
$text = fgets(STDIN);
$text = str_replace(' ', '', ucwords(preg_replace('/[^a-z]/', ' ', strtolower($text))));
echo $text;
?>