Merge pull request #12987 from arnesom/challenge-346-arne-sommer

week 346 Arne Sommer

6 files changed, 194 insertions, 0 deletions

diff --git a/challenge-346/arne-sommer/blog.txt b/challenge-346/arne-sommer/blog.txt
new file mode 100644
index 0000000000..0e6c290166
--- /dev/null
+++ b/challenge-346/arne-sommer/blog.txt
@@ -0,0 +1 @@
+https://raku-musings.com/parenthesised-magic.html
\ No newline at end of file
diff --git a/challenge-346/arne-sommer/raku/ch-1.raku b/challenge-346/arne-sommer/raku/ch-1.raku
new file mode 100755
index 0000000000..5ca9d93fc3
--- /dev/null
+++ b/challenge-346/arne-sommer/raku/ch-1.raku
@@ -0,0 +1,47 @@
+#! /usr/bin/env raku
+
+unit sub MAIN ($str where $str ~~ /^ <[\(\)]>+ $/,
+               :v(:$verbose));
+
+my $balanced := gather
+{
+  for ^($str.chars) -> $i
+  {
+    my $match   = "";
+    my $balance = 0;
+
+    for $str.substr($i).comb -> $char
+    {
+      if $char eq "("
+      {
+        $balance++;
+        $match ~= "(";
+      }
+      elsif $balance == 0
+      {
+	last;
+      }
+      else
+      {
+        $balance--;
+        $match ~= ")";
+      }
+
+      take { index => $i, match => $match } if $balance == 0;
+    }
+  }	
+}
+
+my $longest = 0;
+
+for $balanced -> $curr
+{
+  my $length = $curr<match>.chars;
+  my $is-max = $length > $longest;
+
+  $longest = $length if $is-max;
+
+  say ": Candidate '{ $curr<match> }' at index $curr<index> { $is-max ?? " -> new max $length" !! "" }" if $verbose;
+}
+
+say $longest;
diff --git a/challenge-346/arne-sommer/raku/ch-2.raku b/challenge-346/arne-sommer/raku/ch-2.raku
new file mode 100755
index 0000000000..e5c9b7942d
--- /dev/null
+++ b/challenge-346/arne-sommer/raku/ch-2.raku
@@ -0,0 +1,34 @@
+#! /usr/bin/env raku
+
+unit sub MAIN ($str where $str ~~ /^ <[0..9]>+ $/,
+	       Int $target,
+	       :v(:$verbose));
+
+my $op-size = $str.chars -1;
+my @ops = (("+", "-", "*", "") xx $op-size).flat;
+my @digits = $str.comb;
+my @matches;
+my %seen;
+
+say ": Operators: { @ops.raku }" if $verbose;
+
+for @ops.combinations($op-size) -> @op
+{
+  my $eval     = roundrobin(@digits, @op)>>.join.join;
+
+  next if %seen{$eval}++;
+
+  if $eval ~~ /^0<[0..9]>/ || $eval ~~ /<[+*-]>0<[0..9]>/ 
+  {
+    say ": $eval has a leading zero; skip" if $verbose;
+    next;
+  }
+
+  my $sum      = $eval.EVAL;
+  my $is-equal = $sum == $target;
+  say ": $eval = $sum { $is-equal ?? "OK" !! "(!= $target)" }" if $verbose;
+
+  @matches.push: $eval if $is-equal;
+}
+
+say "({ @matches.map('"' ~ * ~ '"').join(", ") })";
diff --git a/challenge-346/arne-sommer/raku/longest-parenthesis b/challenge-346/arne-sommer/raku/longest-parenthesis
new file mode 100755
index 0000000000..5ca9d93fc3
--- /dev/null
+++ b/challenge-346/arne-sommer/raku/longest-parenthesis
@@ -0,0 +1,47 @@
+#! /usr/bin/env raku
+
+unit sub MAIN ($str where $str ~~ /^ <[\(\)]>+ $/,
+               :v(:$verbose));
+
+my $balanced := gather
+{
+  for ^($str.chars) -> $i
+  {
+    my $match   = "";
+    my $balance = 0;
+
+    for $str.substr($i).comb -> $char
+    {
+      if $char eq "("
+      {
+        $balance++;
+        $match ~= "(";
+      }
+      elsif $balance == 0
+      {
+	last;
+      }
+      else
+      {
+        $balance--;
+        $match ~= ")";
+      }
+
+      take { index => $i, match => $match } if $balance == 0;
+    }
+  }	
+}
+
+my $longest = 0;
+
+for $balanced -> $curr
+{
+  my $length = $curr<match>.chars;
+  my $is-max = $length > $longest;
+
+  $longest = $length if $is-max;
+
+  say ": Candidate '{ $curr<match> }' at index $curr<index> { $is-max ?? " -> new max $length" !! "" }" if $verbose;
+}
+
+say $longest;
diff --git a/challenge-346/arne-sommer/raku/magic-expression b/challenge-346/arne-sommer/raku/magic-expression
new file mode 100755
index 0000000000..fcf8d3a62f
--- /dev/null
+++ b/challenge-346/arne-sommer/raku/magic-expression
@@ -0,0 +1,31 @@
+#! /usr/bin/env raku
+
+unit sub MAIN ($str where $str ~~ /^ <[0..9]>+ $/,
+	       Int $target,
+	       :v(:$verbose));
+
+my $op-size = $str.chars -1;
+my @ops = (("+", "-", "*", "") xx $op-size).flat;
+my @digits = $str.comb;
+my @matches;
+
+say ": Operators: { @ops.raku }" if $verbose;
+
+for @ops.combinations($op-size) -> @op
+{
+  my $eval     = roundrobin(@digits, @op)>>.join.join;
+
+  if $eval ~~ /^0<[0..9]>/ || $eval ~~ /<[+*-]>0<[0..9]>/ 
+  {
+    say ": $eval has a leading zero; skip" if $verbose;
+    next;
+  }
+
+  my $sum      = $eval.EVAL;
+  my $is-equal = $sum == $target;
+  say ": $eval = $sum { $is-equal ?? "OK" !! "(!= $target)" }" if $verbose;
+
+  @matches.push: $eval if $is-equal;
+}
+
+say "({ @matches.unique.map('"' ~ * ~ '"').join(", ") })";
diff --git a/challenge-346/arne-sommer/raku/magic-expression-faster b/challenge-346/arne-sommer/raku/magic-expression-faster
new file mode 100755
index 0000000000..e5c9b7942d
--- /dev/null
+++ b/challenge-346/arne-sommer/raku/magic-expression-faster
@@ -0,0 +1,34 @@
+#! /usr/bin/env raku
+
+unit sub MAIN ($str where $str ~~ /^ <[0..9]>+ $/,
+	       Int $target,
+	       :v(:$verbose));
+
+my $op-size = $str.chars -1;
+my @ops = (("+", "-", "*", "") xx $op-size).flat;
+my @digits = $str.comb;
+my @matches;
+my %seen;
+
+say ": Operators: { @ops.raku }" if $verbose;
+
+for @ops.combinations($op-size) -> @op
+{
+  my $eval     = roundrobin(@digits, @op)>>.join.join;
+
+  next if %seen{$eval}++;
+
+  if $eval ~~ /^0<[0..9]>/ || $eval ~~ /<[+*-]>0<[0..9]>/ 
+  {
+    say ": $eval has a leading zero; skip" if $verbose;
+    next;
+  }
+
+  my $sum      = $eval.EVAL;
+  my $is-equal = $sum == $target;
+  say ": $eval = $sum { $is-equal ?? "OK" !! "(!= $target)" }" if $verbose;
+
+  @matches.push: $eval if $is-equal;
+}
+
+say "({ @matches.map('"' ~ * ~ '"').join(", ") })";