如何在Perl中打印散列哈希值？

Question

我有一个$map{k1}{k2}{k3}{k4}.

如何正确编写循环以打印所有值？以下不起作用.

for my $k1 (sort keys %tripletsCountMap) {
    for my $k2 (sort keys %$tripletsCountMap{k1}){
        for my $k3 (sort keys %$tripletsCountMap{k1}{k2}) {
            for my $k4 (sort keys %$tripletsCountMap{k1}{k3}{k3}){
                print "$k1 $k2 $k3 $k4\n";
            }
        }
    }
}

Answer 1

请注意,k1和之间存在差异$k1.

for my $k1 (sort keys %tripletsCountMap) {
    for my $k2 (sort keys %{ $tripletsCountMap{$k1} }){
        for my $k3 (sort keys %{ $tripletsCountMap{$k1}{$k2} }) {
            for my $k4 (sort keys %{ $tripletsCountMap{$k1}{$k2}{$k3} }){
                printf "$k1 $k2 $k3 $k4: $tripletsCountMap{$k1}{$k2}{$k3}{$k4}\n";
            }
        }
    }
}

更好的是:

use Data::Dumper;
print Dumper \%tripletsCountMap;

而且,你为什么要对键进行排序？我在下面的评论中理解@ysth的观点.除非有一些显式的输出相关要求,否则我只是不习惯在迭代时对哈希的键进行排序.