可以使用列表:: Util :: reduce 在每个***密钥中获取具有最大值的密钥

Can use List::Util::reduce to get the key with the largest value, within each top-level key

use List::Util qw(reduce);

for my $os (keys %info) { 
    my $id_max_length = reduce { 
        $info{$os}{$a} > $info{$os}{$b} ? $a : $b 
    } keys %{$info{$os}};

    say "$os --> $id_max_length --> $info{$os}{$id_max_length}";
}

要在所有键中获得最高价值

To get the highest value among all keys

my ($max_os, $max_id) = 
    map { $_->[0], $_->[1] }
    reduce { $info{$a->[0]}{$a->[1]} > $info{$b->[0]}{$b->[1]} ? $a : $b }
    map { [$_, max_id_for_os($_)] } 
    keys %info;

say "$max_os -> $max_id -> $info{$max_os}{$max_id}";

sub max_id_for_os {
    my ($os) = @_; 
    reduce { $info{$os}{$a} > $info{$os}{$b} ? $a : $b } keys %{$info{$os}}
}

或者，也许更简单，在循环中对***键进行比较

Or, perhaps simpler, compare in the loop over top-level keys

my ($max_os, $max_id) = do {  # initialize
    my ($os) = keys %info;
    $os, (keys %{$info{$os}})[0];
};

for my $os (keys %info) { 
    my $mid = 
        reduce { $info{$os}{$a} > $info{$os}{$b} ? $a : $b } 
        keys %{$info{$os}};

    ($max_os, $max_id) = ($os, $mid) 
        if $info{$os}{$mid} > $info{$max_os}{$max_id};
}

say "Largest: $max_os -> $max_id -> $info{$max_os}{$max_id}";