7 files changed, 118 insertions, 1 deletions

diff --git a/challenge-095/abigail/README.md b/challenge-095/abigail/README.md
index 6ceb4f2573..aead395b0a 100644
--- a/challenge-095/abigail/README.md
+++ b/challenge-095/abigail/README.md
@@ -21,3 +21,28 @@ Output: 0
 
 ### Solutions
 * [Perl](perl/ch-1.pl)
+
+
+## [Task 2](https://perlweeklychallenge.org/blog/perl-weekly-challenge-095/#TASK2)
+
+Write a script to demonstrate `Stack` operations like below:
+
+* `push($n)` - add $n to the stack
+* `pop()` - remove the top element
+* `top()` - get the top element
+* `min()` - return the minimum element
+
+### Example
+~~~~
+my $stack = Stack->new;
+$stack->push(2);
+$stack->push(-1);
+$stack->push(0);
+$stack->pop;       # removes 0
+print $stack->top; # prints -1
+$stack->push(0);
+print $stack->min; # prints -1
+~~~~
+
+### Solutions
+* [Perl](perl/ch-2.pl)
diff --git a/challenge-095/abigail/perl/ch-2.pl b/challenge-095/abigail/perl/ch-2.pl
new file mode 100644
index 0000000000..0d6fe3c042
--- /dev/null
+++ b/challenge-095/abigail/perl/ch-2.pl
@@ -0,0 +1,53 @@
+#!/opt/perl/bin/perl
+
+use 5.032;
+
+use strict;
+use warnings;
+no  warnings 'syntax';
+
+use experimental 'signatures';
+use experimental 'lexical_subs';
+
+#
+# First off, this is a very strange exercise. "push", "pop" and "top"
+# are bog standard stack operations.
+#
+# min, however, is *NOT*. If you want a min operation, a stack is a
+# horrible choice of datastructure, and you'd fail algorithms 101
+# is that were your choice. Use a heap, or some kind of balanced tree.
+#
+
+my $ERROR = "Stack is empty";
+
+my @stack;
+while (<>) {
+    chomp;
+    if    (/^push\s+/p) {push @stack => ${^POSTMATCH}}
+    elsif (/^pop/)      {pop  @stack}
+    elsif (/^top/)      {say  $stack [-1] // $ERROR}
+    elsif (/^min/) {
+        #
+        # Well, since we're asked to demonstrate stack operations
+        # with "min", we won't be using List::Util::min, instead,
+        # we will use a second stack....
+        #
+        my $min;
+        my @other_stack;
+        while (@stack) {
+            my $top = pop @stack;
+            $min = $top if !defined $min || $top < $min;
+            push @other_stack => $top;
+        }
+        say $min // $ERROR;
+        #
+        # Restore the original stack.
+        #
+        push @stack => pop @other_stack while @other_stack;
+    }
+    else {
+        die "Undefined command";
+    }
+}
+
+__END__
diff --git a/challenge-095/abigail/t/ctest.ini b/challenge-095/abigail/t/ctest.ini
index a517632fbf..4e06c03c53 100644
--- a/challenge-095/abigail/t/ctest.ini
+++ b/challenge-095/abigail/t/ctest.ini
@@ -3,4 +3,5 @@
 1-2 = Test decimal dot

 1-3 = Very short inputs

 1-4 = Unicode and script runs

-2-1 = Example 1

+2-1 = Given example

+2-2 = Test empty stack

diff --git a/challenge-095/abigail/t/input-2-1 b/challenge-095/abigail/t/input-2-1
new file mode 100644
index 0000000000..2fd42265cf
--- /dev/null
+++ b/challenge-095/abigail/t/input-2-1
@@ -0,0 +1,7 @@
+push 2
+push -1
+push 0
+pop
+top
+push 0
+min
diff --git a/challenge-095/abigail/t/input-2-2 b/challenge-095/abigail/t/input-2-2
new file mode 100644
index 0000000000..ccdf552d6b
--- /dev/null
+++ b/challenge-095/abigail/t/input-2-2
@@ -0,0 +1,23 @@
+top
+min
+push 1
+push 2
+push 3
+push 4
+min
+pop
+min
+top
+push -3
+push -2
+push -1
+min
+pop
+pop
+pop
+pop
+pop
+pop
+pop
+pop
+pop
diff --git a/challenge-095/abigail/t/output-2-1.exp b/challenge-095/abigail/t/output-2-1.exp
new file mode 100644
index 0000000000..343ee5c2f6
--- /dev/null
+++ b/challenge-095/abigail/t/output-2-1.exp
@@ -0,0 +1,2 @@
+-1
+-1
diff --git a/challenge-095/abigail/t/output-2-2.exp b/challenge-095/abigail/t/output-2-2.exp
new file mode 100644
index 0000000000..67f67b4693
--- /dev/null
+++ b/challenge-095/abigail/t/output-2-2.exp
@@ -0,0 +1,6 @@
+Stack is empty
+Stack is empty
+1
+1
+3
+-3