}
public function key()
{
return $this->key;
}
public function next()
{
if ($this->value === 0) {
$this->value = 1;
} else {
$old = $this->value;
$this->value += $this->sum;
$this->sum = $old;
}
$this->key++;
}
public function valid()
{
return $this->value < PHP_INT_MAX;
}
}
// print the Fibonacci numbers until PHP_INT_MAX
foreach ($test = new Fibonacci() as $key => $value) {
printf("%d) %d\n", $key, $value);
}
// print the first 10 Fibonacci's numbers
$num = new Fibonacci();
for ($i = 0; $i < 10; $i++) {
printf("%d) %d\n", $i, $num->current());
$num->next();
}
public function current()
{
return $this->value;
}
public function key()
{
return $this->key;
}
public function next()
{
if ($this->value === 0) {
$this->value = 1;
} else {
$old = $this->value;
$this->value += $this->sum;
$this->sum = $old;
}
$this->key++;
}
public function valid()
{
return true;
}
}
// check the first 10 Fibonacci's numbers
$num = new Fibonacci();
$correct = array(0, 1, 1, 2, 3, 5, 8, 13, 21, 34);
for ($i = 0; $i < 10; $i++) {
printf("%s<br>", $num->current() === $correct[$i] ? 'OK ' : 'ERROR');
$num->next();
}