fork(2) download
copy 
  1. <?php
  2.  
  3. 	function fibonacci( $n ) {
  4.     	$V5   = sqrt( 5 );
  5. 		$Phi  = ( 1 + $V5 ) / 2;
  6. 		$iPhi = -1 / $Phi;
  7.     	return round( ( pow( $Phi, $n ) - pow( $iPhi, $n ) ) / $V5 );
  8. 	}
  9.  
  10. 	echo fibonacci( 1 ).PHP_EOL;
  11. 	echo fibonacci( 5 ).PHP_EOL;
  12. 	echo fibonacci( 100 ).PHP_EOL;
  13.  
  14. ?>
  15.  
Success #stdin #stdout 0.02s 52432KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
1
5
3.5422484817926E+20
https://ideone.com/epYP51
language:
PHP (php 7.3.5)
created:
8 years ago
visibility:
secret

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!