Either you don't need $cnt, or you don't need to iterate over the indexes. 
for (0..$#array){
    if ($_ % 20 == 19){
        print OUT "$array[$_]\n";
    }
    else{
        print OUT "$array[$_] ";
    }    
}

[download]
for (@array){
    if (++$cnt % 20 == 0){
        print OUT "$_\n";
    }
    else{
        print OUT "$_ ";
    }    
}

[download]

It's probably worth noting the last line has a trailing space and isn't terminated.

In reply to Re^2: printing 20 characters in a line. by ikegami
in thread printing 20 characters in a line. by heidi

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