I am new to programming and hence I am stuck on a basic level problem.

Following is code I wrote for comparison. But the result I get does not make sense to me. I would appreciate if someone could tell me what is going wrong. 

There are two arrays: @array1 , @array2 of unequal length. 

I wish to compare both and list down values not present in @array1.

my %temp = map {$_,$_}@array2;
for (@array1){
next if exists $temp{$_};
open (FILE, "&gt;&gt;/filename") or die "$!";
print FILE "$_\n";
close(FILE);
}



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