TheAlgorithms-PHP/Searches/FibonacciSearch.php

24 lines
458 B
PHP

<?php
/*
* Function to find nth number in Fibonacci sequence.
* Uses a version of memoization and runs very fast!
*/
/**
* @param int $n position to check
* @param array $m array to store solved trees
*/
function fibonacciPosition(int $n, array &$m = [])
{
if(isset($m[$n])) return $m[$n];
if($n < 2) return $n;
$m[$n] = fibonacciPosition($n - 1, $m) + fibonacciPosition($n - 2, $m);
return $m[$n];
}
print fibonacciPosition(59);