Add all README.org files

These files generate README, it's better to commit them than keep in
`.gitignore'.

1 files changed, 54 insertions, 0 deletions

diff --git a/challenge-078/andinus/README.org b/challenge-078/andinus/README.org
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+#+SETUPFILE: ~/.emacs.d/org-templates/level-2.org
+#+HTML_LINK_UP: ../../writings/
+#+OPTIONS: toc:2
+#+EXPORT_FILE_NAME: index
+#+TITLE: Challenge 078
+
+* Task 1 - Leader Element
+You are given an array @A containing distinct integers.
+
+Write a script to find all leader elements in the array @A. Print (0) if
+none found.
+
+- An element is leader if it is greater than all the elements to its
+  right side.
+** Perl
+- Program: [[file:perl/ch-1.pl]]
+
+We take input from =@ARGV=, loop over it. And then we loop over the
+elements at right, goto next if =$arg= is less than =$elm=. This will push
+all the leader elements to =@leader=.
+#+BEGIN_SRC perl
+my @leader;
+MAIN: while (my $arg = shift @ARGV) {
+    foreach my $elm (@ARGV) {
+        next MAIN if $arg < $elm;
+    }
+    push @leader, $arg;
+}
+#+END_SRC
+* Task 2 - Left Rotation
+You are given array @A containing positive numbers and @B containing one
+or more indices from the array @A.
+
+Write a script to left rotate @A so that the number at the first index
+of @B becomes the first element in the array. Similary, left rotate @A
+again so that the number at the second index of @B becomes the first
+element in the array.
+** Perl
+- Program: [[file:perl/ch-2.pl]]
+
+Loop over =@B= & then rotate the elements. Same could've been done with
+Left Rotation, I find this easier to understand.
+#+BEGIN_SRC perl
+my @A = qw(10 20 30 40 50);
+my @B = qw(3 4);
+
+foreach (@B) {
+    my @tmp = @A;
+    foreach (1 ... scalar @tmp - $_) {
+        unshift @tmp, pop @tmp;
+    }
+    print join(', ', @tmp), "\n";
+}
+#+END_SRC