Merge pull request #9203 from jacoby/master

Fixed and blogged 246

3 files changed, 33 insertions, 18 deletions

diff --git a/challenge-246/dave-jacoby/blog.txt b/challenge-246/dave-jacoby/blog.txt
new file mode 100644
index 0000000000..dad54dfbf8
--- /dev/null
+++ b/challenge-246/dave-jacoby/blog.txt
@@ -0,0 +1 @@
+https://jacoby.github.io/2023/12/05/make-it-unique-weekly-challenge-246.html
diff --git a/challenge-246/dave-jacoby/perl/ch-1.pl b/challenge-246/dave-jacoby/perl/ch-1.pl
index 6b58ba3912..6b670775a8 100644
--- a/challenge-246/dave-jacoby/perl/ch-1.pl
+++ b/challenge-246/dave-jacoby/perl/ch-1.pl
@@ -4,11 +4,31 @@ use strict;
 use warnings;
 use experimental qw{ say postderef signatures state };
 
-say join "\n", 
-    sort { $a <=> $b }      # and the example is sorted numerically, so we will
-    map { 1 + int rand 49 } # which are random and between 1 and 49
-                            # but int rand ( n ) will give a number between 0 and n-1
-                            # so adding 1 will put it at the right range
-    1 .. 6;                 # we want six numbers
+my %hash;
 
 
+# Write a script that outputs six unique random integers 
+# from the range 1 to 49.
+
+# I had missed 'unique', which means we have to be sure we
+# deal with duplicates. Use the random number as keys to a hash
+# and you won't get duplicates.
+
+# Adding the numeric sort just makes it pretty.
+
+while ( scalar keys %hash < 6 ) {
+    my $n = 1 + int rand 49;
+    $hash{$n} = 1;
+}
+
+say join "\n", sort { $a <=> $b } keys %hash;
+
+# And here is my first pass, which ignored "unique". 
+# Because of that, it was very simple.
+
+# say join "\n",
+#     sort { $a <=> $b }      # and the example is sorted numerically, so we will
+#     map { 1 + int rand 49 } # which are random and between 1 and 49
+#                             # but int rand ( n ) will give a number between 0 and n-1
+#                             # so adding 1 will put it at the right range
+#     1 .. 6;                 # we want six numbers
diff --git a/challenge-246/dave-jacoby/perl/ch-2.pl b/challenge-246/dave-jacoby/perl/ch-2.pl
index 2cf6806510..9ff50ee947 100644
--- a/challenge-246/dave-jacoby/perl/ch-2.pl
+++ b/challenge-246/dave-jacoby/perl/ch-2.pl
@@ -4,8 +4,6 @@ use strict;
 use warnings;
 use experimental qw{ say postderef signatures state };
 
-use Algorithm::Combinatorics qw{ variations };
-
 my @examples = (
 
     [ 1, 1, 2, 3,  5 ],
@@ -25,16 +23,12 @@ for my $e (@examples) {
 
 sub lrso (@input) {
 OUTER: for my $n ( 2 .. -1 + scalar @input ) {
-        for my $p ( 1 .. 100 ) {
-            for my $pp ( 1, -1 ) {
-                my $ppp = ( $p * $pp ) * $input[ $n - 2 ];
-                for my $q ( 1 .. 100 ) {
-                    for my $qq ( 1, -1 ) {
-                        my $qqq = ( $q * $qq ) * $input[ $n - 1 ];
-                        my $rrr = $ppp + $qqq;
-                        next OUTER if $rrr == $input[$n];
-                    }
-                }
+        for my $p ( -100 .. 100 ) {
+            my $pp = $p * $input[ $n - 2 ];
+            for my $q ( -100 .. 100 ) {
+                my $qq = $q * $input[ $n - 1 ];
+                my $rr = $pp + $qq;
+                next OUTER if $rr == $input[$n];
             }
         }
         return 'false';