#!/usr/bin/perl
use warnings;
use strict;

my $n = <>; # read the input

my $r = '';
my $p = 2;
while ($n > 1) {
    if ($n % $p == 0) {
        $r .= "$p, ";  # . is the concatenation operator
        $n /= $p;
    } else {
        ++$p;
    }
}
print "$r\n";
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