perl将十进制变换为64进制的方法

perl将十进制转换为64进制的方法
#!/usr/bin/perl
# 将十进制转换为64进制的方法
$arr="0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ+/";
sub ch_num_to_64(){
#参数
my @list_data=();
my $res_data;
my $res =$_[0];
if (int($res)==0){
$res_data=0;
}
my $res2;
    while($res != 0)
   {
         $res2 = $res%64;
         push(@list_data,substr($arr,$res2,1));
         $res = int($res/64);
   }
   @list_data=reverse (@list_data);
   foreach $item (@list_data){
      $res_data.=$item;
   }
   return $res_data;
}
$rest64=&ch_num_to_64(129);
print "the result is : " . $rest64 . "\n";
{
    return $des;
}
$_ = $src;
if (/[\d a-f A-F]{8}/)
{
my $tmp;
$tmp=hex (substr($src,0,2));
$des=$tmp;
$tmp=hex (substr($src,2,2));
$des=$des . "." . "$tmp";
$tmp=hex (substr($src,4,2));
$des=$des . "." . "$tmp";
$tmp=hex (substr($src,6,2));
$des=$des . "." . "$tmp";
}

return $des;
}

print &trans_ip("AE0AB2CA") . "\n";   #174.10.178.202