use strict;
use warnings;
use FileHandle;

for (my $i = 0; $i < @myArr; $i++) {
    my $value = $myArr[$i];
    my $index = $i + 1;
    my $file  = "file${index}";
    write_value_to_file($value, $file);
}

sub write_value_to_file {
    my ($val, $fname) = @_;
    my $fh = new FileHandle;
    open($fh, ">", $fname) or die "unable to write $fname ($!)\n";
    print $fh "$val\n";
    close $fh;
}