Question

另一个哈希包含名称作为键（由_分割）并且有4个部分（我比较前三个部分）。该值是一个字符串，其长度需要比较，如果名称相同并且已经存在于散列（前三部分）中，我需要保持字符串的长度最长，如果长度相等，我不会关心它保留哪一个。我知道迭代它会在删除键值对时产生问题。

 my %temphash=();
 %temphash=%anotherhash;
 foreach my $tempkey(keys %temphash){
        my @tempkey_splitted = split /\_/, $tempkey;
        my $tempkey_newfamily = $tempkey_splitted[0];
        my $tempkey_newgenera = $tempkey_splitted[1];
        my $tempkey_newspecies = $tempkey_splitted[2];
        my $tempkey_catstring ="$tempkey_newfamily"."_$tempkey_newgenera"."_$tempkey_newspecies";
        my $sequence_realkey="";
        my $sequence_tempkey="";
        my $length_realkey="";
        my $length_tempkey="";
        if ($realkey_catstring eq $tempkey_catstring){
            $sequence_realkey = $anotherhash{$realkey};
            $length_realkey = length($sequence_realkey);
            #print "$anotherhash{$realkey}";
            #print "$length_realkey";
            $sequence_tempkey = $temphash{$tempkey};
            #print "$anotherhash{$tempkey}";
            $length_tempkey = length($sequence_tempkey);
            # print "$length_tempkey";

            if($length_realkey>$length_tempkey){
                delete($temphash{$tempkey});
               #print ">$realkey\n$anotherhash{$realkey}\n\n";
                }
            elsif($length_tempkey>$length_realkey){
               delete($temphash{$realkey});
               #print ">$tempkey\n$anotherhash{$tempkey}\n\n";
                }
            elsif($length_tempkey eq $length_realkey){
                delete($temphash{$realkey});
                }
            }
        else{
             print "do nothing"; 
            }
        }
    }

Answer 1

您的代码非常复杂，但我认为下面的示例代码可以满足您的需求。它的工作原理是将%anotherhash的内容（请不要对变量使用这些可怕的无意义名称）一次复制到%temphash一个元素，并且只有在新的%anotherhash的值超过%temphash

my %temphash;

while (my ($key, $val) = each %anotherhash) {

  my @key = split /_/, $key;
  my $tempkey = join '_', @key[0,1,2];
  my $tempval = $temphash{$tempkey};

  unless (defined $tempval and length $tempval >= length $val) {
    $temphash{$tempkey} = $val;
  }
}

在hash perl中删除的问题

1 个答案: