Merge pull request #1918 from Firedrake/rogerbw-challenge-068

Solutions for challenge #68

2 files changed, 72 insertions, 0 deletions

diff --git a/challenge-068/roger-bell-west/perl/ch-1.pl b/challenge-068/roger-bell-west/perl/ch-1.pl
new file mode 100644
index 0000000000..3c6e4166c1
--- /dev/null
+++ b/challenge-068/roger-bell-west/perl/ch-1.pl
@@ -0,0 +1,42 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+
+use Test::More tests => 2;
+
+is_deeply(zm([[1,0,1],[1,1,1],[1,1,1]]),
+          [[0,0,0],[1,0,1],[1,0,1]],
+          'example 1',
+            );
+is_deeply(zm([[1,0,1],[1,1,1],[1,0,1]]),
+          [[0,0,0],[1,0,1],[0,0,0]],
+          'example 2',
+            );
+
+sub zm {
+  my $in=shift;
+  my $a=scalar @{$in}-1;
+  my $b=scalar @{$in->[0]}-1;
+  my %seta;
+  my %setb;
+  foreach my $ai (0..$a) {
+    foreach my $bi (0..$b) {
+      if ($in->[$ai][$bi]==0) {
+        $seta{$ai}=1;
+        $setb{$bi}=1;
+      }
+    }
+  }
+  foreach my $aa (keys %seta) {
+    foreach my $bi (0..$b) {
+      $in->[$aa][$bi]=0;
+    }
+  }
+  foreach my $bb (keys %setb) {
+    foreach my $ai (0..$a) {
+      $in->[$ai][$bb]=0;
+    }
+  }
+  return $in;
+}
diff --git a/challenge-068/roger-bell-west/perl/ch-2.pl b/challenge-068/roger-bell-west/perl/ch-2.pl
new file mode 100644
index 0000000000..dbf7eec8c6
--- /dev/null
+++ b/challenge-068/roger-bell-west/perl/ch-2.pl
@@ -0,0 +1,30 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+
+use Test::More tests => 2;
+
+is_deeply(rl([1,2,3,4]),
+          [1,4,2,3],
+          'example 1',
+            );
+is_deeply(rl([1,2,3,4,5]),
+          [1,5,2,4,3],
+          'example 2',
+            );
+
+sub rl {
+  my $list=shift;
+  my $n=scalar @{$list};
+  my $nx=$n-1;
+  my @i;
+  foreach my $ni (0..int($nx/2)) {
+    push @i,$ni,$nx-$ni;
+  }
+  if ($i[-1] == $i[-2]) {
+    pop @i;
+  }
+  @{$list}=@{$list}[@i];
+  return $list;
+}