perl 读取一个文件，然后把读出来的数据写进另一个文件中去！

本人初学perl, 做基于人工智能的蛋白质结构预测课题，最近遇到一个问题，需要把200个单独的标准fasta 文件(DSBs_10MHA.fasta) 整合到一个Total.fasta文件中，本以为很容易却一直报错，网上查找解决措施未果，自己最后用数组解决循环迭代。

详细过程如下

1. 输入及输出，

输入：DSBs_id_list.txt，200个DSBs_XXXXX.fasta,
输出：Total200.fasta.

2. 报错代码

#!/usr/bin/perl -w

open TOTAL,">>total.fasta" or die " can't creat file";
open ID_LIST,"<DSBs_id_list.txt" or die " can't read file";
foreach my $id (<ID_LIST>)
{
   open FASTA,"<seq_fasta/$id.fasta" or die " can't read file";;
   while (<FASTA>)
   {
     print TOTAL "$_\n";
    }
    close FASTA;
 }
 close ID_LIST;
 close TOTAL;

报错

can’t read file at merge_fasta.pl line 7, <ID_LIST> line 754.

网络解决方案;
~~百度知道：~~ https://zhidao.baidu.com/question/568388108.html
~~Stack Overflow：~~ https://stackoverflow.com/questions/15014763/readline-on-closed-filehandle
~~~~然而这些解决方案本人亲试，并无卵用~~~ ~
最终我的解决方案;

用数组代替迭代循环

!/usr/bin/perl -w
####################################
#**用数组代替迭代循环**
####################################

open TOTAL,">>total.fasta" or die " can't creat file";

$ID_LIST = "<DSBs_id_list.txt";
open(IN, $ID_LIST);
@ID_ARRAY = <IN>;
close(IN);
chomp(@ID_ARRAY);

my $id=0 ;
my $cnt = @ID_ARRAY;

while ($id < $cnt)
{
  my $complex_id = $ID_ARRAY[$id];
  
  $id++;
  
  $fasta= "<seq_fasta/".$complex_id.".fasta";
  open(IN, $fasta);
  @FASTA = <IN>;
  close(IN);
  chomp(@FASTA);
  
  print TOTAL "$FASTA[0]\n$FASTA[1]\n";
  #  FASTA 标准文件格式共两行
}

close TOTAL;