# Largest prime factor

*Author: Gerhard R*

https://projecteuler.net/problem=3

The prime factors of 13195 are 5, 7, 13 and 29.

What is the largest prime factor of the number 600851475143 ?

Source code: prob003-gerdr.pl

use v6; sub largest-prime-factor($n is copy) { for 2, 3, *+2 ... * { while $n %% $_ { $n div= $_; return $_ if $_ > $n; } } } say largest-prime-factor(600_851_475_143);