Combine columns from multiple files

Shell Programming and Scripting
1

Can anybody help on the script to combine/concatenate columns from multiple files

input1

4 135
5 185
6 85
11 30
16 72
17 30
21 52
22 76

input2

2 50
4 50
6 33
8 62
10 25
12 46
14 42
15 46

output

nr input1 input2
2          50
4  135     50
5  185
6  85      33
8          62
10         25
11  30
12         46
14         42
15         46
16  72
17  30
21  52
22  76
2

look into the join command

join -a 1 -a 2 file1 file2
3

Here is a try in perl (works for more than two input files, too):
Save code as comb.pl and call with: perl comb.pl input1 input2 ...

#!/usr/bin/perl
exit if $#ARGV < 0;
for ($i=0; $i<=$#ARGV; $i++) {
  push @init, "";
}
$n=0;
push @header, "nr";
while ($ARG = shift) {
  push @header, $ARG;
  open(IN, $ARG) || die "cannot open $ARG";
  while (<IN>) {
    chomp;
    split;
    $entry{@_[0]} = [ @init ] if !defined($entry{@_[0]});
    $entry{@_[0]}[$n] = @_[1];
  }
  $n++;
}
for ($i=0; $i<=$n; $i++) {
  printf("%-10s", $header[$i]);
}
print "\n";
foreach $key (sort {$a <=> $b} keys(%entry)) {
  printf("%-10s", $key);
  for ($i=0; $i<$n; $i++) {
    printf("%-10s",${entry{$key}}[$i]);
  }
  print "\n";
}