Perl - 通过阵列散列的Roundrobin

Question

my %aggrs_by_node = (
    node1 => ['a1_1','a1_2'], 
    node2 => ['a2_1','a2_2','a2_3'], 
    hello => ['ah_1','ah_2','ah_3'], 
    node3 => ['a3_1','a3_2','a3_3','a3_4'], 
); 

任何人有任何建议，我怎么可以通过这个散列中的所有数组元素循环，同时避免密钥hello？

Iteration 1 = a1_1 
Iteration 2 = a2_1 
Iteration 3 = a3_1 
Iteration 4 = a1_2 
Iteration 5 = a2_2 
Iteration 6 = a3_2 
Iteration 7 = a1_1 
Iteration 8 = a2_3 

等等

Answer 1

这套短节目做你的要求。它将索引散列到每个数组中。

我已经在数组@keys中使用了散列键的单独排序列表，因为直接从散列中取出它们将导致不可预测的顺序，并且看起来您需要按特定顺序输出。

use strict; 
use warnings; 

my %aggrs_by_node = (
    node1 => ['a1_1','a1_2'], 
    node2 => ['a2_1','a2_2','a2_3'], 
    hello => ['ah_1','ah_2','ah_3'], 
    node3 => ['a3_1','a3_2','a3_3','a3_4'], 
); 

my %indices = map { $_ => 0 } keys %aggrs_by_node; 
delete $indices{hello}; 
my @keys = sort keys %indices; 

for my $iter (1 .. 20) { 
    my $key = $keys[($iter - 1) % @keys]; 
    my $val = $aggrs_by_node{$key}[$indices{$key}]; 
    $indices{$key} = ($indices{$key} + 1) % @{ $aggrs_by_node{$key} }; 
    printf "Iteration %d = %s\n", $iter, $val; 
} 

输出

Iteration 1 = a1_1 
Iteration 2 = a2_1 
Iteration 3 = a3_1 
Iteration 4 = a1_2 
Iteration 5 = a2_2 
Iteration 6 = a3_2 
Iteration 7 = a1_1 
Iteration 8 = a2_3 
Iteration 9 = a3_3 
Iteration 10 = a1_2 
Iteration 11 = a2_1 
Iteration 12 = a3_4 
Iteration 13 = a1_1 
Iteration 14 = a2_2 
Iteration 15 = a3_1 
Iteration 16 = a1_2 
Iteration 17 = a2_3 
Iteration 18 = a3_2 
Iteration 19 = a1_1 
Iteration 20 = a2_1