Merge pull request #350 from adamcrussell/challenge-015

solutions for challenge 015

3 files changed, 107 insertions, 0 deletions

diff --git a/challenge-015/adam-russell/blog.txt b/challenge-015/adam-russell/blog.txt
new file mode 100644
index 0000000000..ba4dcd32ab
--- /dev/null
+++ b/challenge-015/adam-russell/blog.txt
@@ -0,0 +1 @@
+https://adamcrussell.livejournal.com/5175.html
diff --git a/challenge-015/adam-russell/perl5/ch-1.pl b/challenge-015/adam-russell/perl5/ch-1.pl
new file mode 100644
index 0000000000..3fcfef5868
--- /dev/null
+++ b/challenge-015/adam-russell/perl5/ch-1.pl
@@ -0,0 +1,68 @@
+use strict;
+use warnings;
+##
+# Write a script to generate first 10 strong and weak prime numbers.
+##
+use boolean; 
+use LWP::UserAgent;
+use constant PRIME_URL => "http://primes.utm.edu/lists/small/100000.txt";
+
+sub get_primes{
+    my @primes;  
+    my $ua = new LWP::UserAgent(
+        ssl_opts => {verify_hostname => 0}
+    );
+    my $response = $ua->get(PRIME_URL);
+    my @lines = split(/\n/,$response->decoded_content);  
+    foreach my $line (@lines){
+        my @p = split(/\s+/, $line);
+        unless(@p < 10){
+            push @primes, @p[1..(@p - 1)]; 
+        }  
+    }
+    return @primes; 
+}
+
+sub find_strong_prime{
+    my($n_prev, $n, $n_next) = @_;
+    if($n > (($n_prev + $n_next) / 2)){
+        return true; 
+    }   
+    return false; 
+} 
+
+sub find_weak_prime{
+    my($n_prev, $n, $n_next) = @_;
+    if($n < (($n_prev + $n_next) / 2)){
+        return true; 
+    }   
+    return false; 
+} 
+##
+# Main
+##
+my(@weak, @strong);
+my @primes = get_primes(); 
+my @test;
+push @test, shift @primes; 
+push @test, shift @primes; 
+while((@weak < 10 || @strong < 10) && @primes > 3){
+    push @test, shift @primes; 
+    if(find_strong_prime(@test) && @strong < 10){
+        push @strong, $test[1]; 
+    }  
+    if(find_weak_prime(@test) && @weak < 10){
+        push @weak, $test[1]; 
+    }  
+    shift @test; 
+} 
+if(@weak == 10 && @strong == 10){ 
+    print "\tStrong\t\tWeak\n";
+    print "\t======\t\t====\n";
+    foreach my $i (0..9){
+        print "$i:\t$strong[$i]\t\t$weak[$i]\n";
+    }  
+}
+else{ 
+    print "Ten strong/weak primes were not found in the first 100,000 primes.\n";  
+} 
diff --git a/challenge-015/adam-russell/perl5/ch-2.pl b/challenge-015/adam-russell/perl5/ch-2.pl
new file mode 100644
index 0000000000..b359e0e628
--- /dev/null
+++ b/challenge-015/adam-russell/perl5/ch-2.pl
@@ -0,0 +1,38 @@
+use strict;
+use warnings;
+##
+# Write a script to implement Vigenère cipher. 
+# The script should be able to encode and decode.
+##
+use constant KEYWORD => "perl";  
+
+sub encode{
+    my($plaintext) = @_;
+    my $encrypted = "";
+    my @characters = split(//, $plaintext);
+    my @key = split(//, KEYWORD x ((length($plaintext) / length(KEYWORD)) + 1));
+    foreach my $c (@characters){
+       my $e = ((ord(lc($c)) - ord("a")) + (ord(shift @key) - ord("a"))) % 26;   
+       $encrypted .= chr($e + ord("a"));  
+    }  
+    return $encrypted; 
+}
+
+sub decode{
+    my($encrypted) = @_;
+    my $plaintext = "";
+    my @characters = split(//, $encrypted);
+    my @key = split(//, KEYWORD x ((length($encrypted) / length(KEYWORD)) + 1));
+    foreach my $c (@characters){
+       my $e = ((ord(lc($c)) - ord("a")) - (ord(shift @key) - ord("a"))) % 26;   
+       $plaintext .= chr($e + ord("a"));  
+    }  
+    return $plaintext; 
+
+}
+
+##
+# Main
+## 
+print "ATTACKATDAWN is encoded as " . encode("ATTACKATDAWN") . "\n";
+print "PXKLRORESENY is decoded as " . decode("PXKLRORESENY") . "\n";