按散列Perl的值散列排序

Question

假设我有一个哈希数据结构，构造如下：

%HoH => (
     flintstones => {
               family_members    => "fred;wilma;pebbles;dino",
               number_of_members => 4,
     },
     jetsons => {
               family_members    => "george;jane;elroy",
               number_of_members => 3,
     },
     simpsons => {
               family_members    => "homer;marge;bart;lisa;maggie",
               number_of_members => 5,
     },

)

在这种情况下，如何按值number_of_members从最大到最小对键进行排序？然后我想打印出最高的两个。这是一个大致的想法，但我知道这是错误的：

foreach $value (
    sort {
    $HoH{$a}{$number_of_members} cmp $HoH{$b}{$number_of_members}
    } keys %HoH)
my $count = 0;
while ($key, $value) = each %HoH) {
    if (count <= 2){
        print "${HoH}{$key}\t$key{$value}";
    }
}
continue {
    $count++;
};

我想要打印代码（空格以制表符分隔）：

simpsons    homer;marge;bart;lisa;maggie
flintstones    fred;wilma;pebbles;dino

Answer 1

你在正确的轨道上。在散列中使用$a和$b，并以数字方式比较值（）

打印时，我发现将键存储在一个数组中并使用数组切片来访问它们是最简单的。

use strict;
use warnings;

my %HoH = (
     flintstones => {
               family_members    => "fred;wilma;pebbles;dino",
               number_of_members => 4,
     },
     jetsons => {
               family_members    => "george;jane;elroy",
               number_of_members => 3,
     },
     simpsons => {
               family_members    => "homer;marge;bart;lisa;maggie",
               number_of_members => 5,
     },    
);
my @sorted = sort { $HoH{$b}{'number_of_members'} <=> 
                    $HoH{$a}{'number_of_members'} } keys %HoH;

for (@sorted[0,1]) {   # print only first two
    print join("\t", $_, $HoH{$_}{'family_members'}), "\n";
}

输出：

simpsons        homer;marge;bart;lisa;maggie
flintstones     fred;wilma;pebbles;dino