#!/usr/bin/perl
use strict;
use warnings;
my $str="30 30 36 33 36 36 36 33 36 34 26 24 21 17 17 23 27 27 31 31 3
+4 33 33 33 36 36 37 38 38 38 38 38 35 40 34 34 34 31 37 36 37 37 40 4
+0 49 40 40 40 40 40 40 40 40 33 30 30 30 30 30 42 45 45 45 45 45 49 4
+2 42";
open (OUT,">format.out");
my @array=split(/ /,$str);

for (0..19){
    print OUT "$array[$_] ";
}
close(OUT);
[download]

Updated after the reply from heidi

I misunderstood the question, thanks for the reply heidi. So here is the code you needed,

#!/usr/bin/perl
use strict;
use warnings;
my $str="30 30 36 33 36 36 36 33 36 34 26 24 21 17 17 23 27 27 31 31 3
+4 33 33 33 36 36 37 38 38 38 38 38 35 40 34 34 34 31 37 36 37 37 40 4
+0 49 40 40 40 40 40 40 40 40 33 30 30 30 30 30 42 45 45 45 45 45 49 4
+2 42";
open (OUT,">format.out");
my @array=split(/ /,$str);
my $cnt=0;
foreach (0..$#array){
    ++$cnt;
    if ($cnt % 20 == 0){
        print OUT "$array[$_]\n";
    }
    else{
        print OUT "$array[$_] ";
    }    
}
close(OUT);
[download]

Punitha