I've been running through examples in the PERL textbook. This example asks me to find all the prime numbers up to the number I enter via STDIN. The code looks like this. it will print "1 2 35791113151719" if my stdIN is 21. How do I make sure that there is a space between each number? The book doesn't address this. 

#! /usr/bin/perl
#prime_number.pl
use warnings;
use strict;

print "To what number would you like to calculate the primes?", "\n";
my $n = <>;
my $i = 3;
print "1 2  ";

#keep executing search until the num ($i) reaches given value ($n)

OUTER: while ($i <= $n) {
    #for each iteration, begin division by 2
    
    my $num = 2;
    
    #check to see if value is prime
    
    for (1 .. $i){
        
        if (($i % $num == 0) and ($i != $num)) {
        
        #if not, check next num
        
        $i++;
        
        next OUTER;
        }
        if ($num > sqrt($i)) {
        print "$i";
        $i++;
        next OUTER;
    }    
    $num++;
 }
 }

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In reply to Spaces between outputs. by CPTQuesoXI

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