Hello wise Monks; i am trying to concatenate the lines of 2 files and came up with this simple code 
my (@In, $In, @Out, $Out, $InFile, $OutFile);                         
+       # declare variables
    open $InFile, "<", "e:/File1.txt";            # open the exported 
+file in read mode
    open $OutFile, ">>", "e:/File2";
    @In = <$InFile>;
    @Out = <$OutFile>;
    close $InFile;
    close $OutFile;
    for my $k ( 0 .. $#In ) {
        $Out[$k] = "$Out[$k],$In[$k]";
}
    open $OutFile, ">", "e:/File2.txt";            # open the outfile,
+ deleting all content (writemode)
    print $OutFile @Out;
    close $OutFile;

[download]

but i am getting the error: "Use of uninitialized value within @Out in concatenation(.) or string at join.pl"

I know, my programming skills are bad but please, i dont know any other way.

In reply to Why isn't this simple method to join elements of 2 arrays not working by Axlex

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