Sorting 按值排序散列

这不是我填充哈希的方式。为了便于阅读，以下是其内容，键位于固定长度的字符串上：

my %country_hash = (
  "001 Sample Name   New Zealand" => "NEW ZEALAND",
  "002 Samp2 Nam2    Zimbabwe   " => "ZIMBABWE",
  "003 SSS NNN       Australia  " => "AUSTRALIA",
  "004 John Sample   Philippines" => "PHILIPPINES,
);

我想得到基于值的排序键。所以我的期望是：

"003 SSS NNN       Australia  "
"001 Sample Name   New Zealand"
"004 John Sample   Philippines"
"002 Samp2 Nam2    Zimbabwe   "

我所做的：

foreach my $line( sort {$country_hash{$a} <=> $country_hash{$b} or $a cmp $b} keys %country_hash ){
  print "$line\n";
}

foreach my$行（排序{$country_hash{$a}$country_hash{$b}或$a cmp$b}键%country_hash）{
打印“$line\n”；
}

还有,； （我怀疑这是否会解决问题，但无论如何）

my@sorted=sort{$country\u hash{$a}$country\u hash{$b}关键字%country\u hash；
foreach my$行（@sorted）{
打印“$line\n”；
}

---

他们两个都没有正确排序。我希望有人能帮忙。

如果你使用了

警告

，你会被告知

是错误的操作员；它用于数值比较。使用

cmp

进行字符串比较。参考

这张照片是：

003 SSS NNN       Australia  
001 Sample Name   New Zealand
004 John Sample   Philippines
002 Samp2 Nam2    Zimbabwe   

---

这也可以工作（没有额外的阵列）：

use warnings;
use strict;

my %country_hash = (
  "001 Sample Name   New Zealand" => "NEW ZEALAND",
  "002 Samp2 Nam2    Zimbabwe   " => "ZIMBABWE",
  "003 SSS NNN       Australia  " => "AUSTRALIA",
  "004 John Sample   Philippines" => "PHILIPPINES",
);

my @sorted = sort { $country_hash{$a} cmp $country_hash{$b} } keys %country_hash;
foreach my $line(@sorted){
    print "$line\n";
}

003 SSS NNN       Australia  
001 Sample Name   New Zealand
004 John Sample   Philippines
002 Samp2 Nam2    Zimbabwe   

foreach my $line (sort {$country_hash{$a} cmp $country_hash{$b}} keys %country_hash) {
    print "$line\n";
}