my $num = $ARGV[0];
my $den = $ARGV[1];
my $rem = $num%$den;
my $rec;
my $rec_exists;
while ($rem) {
    $rem *= 10;
    my $quotient = int($rem/$den);
    if($rec =~ m/$quotient/) {
        $rec_exists = 1;
        last;
    }
    $rec .= int($rem/$den);

    $rem %= $den;
}
if ($rec_exists) {
    print "recurrence exists: $rec \n";
}
else
{
    print "no recurrence ..\n";
}
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