From 6b214a53243ca546b5f84656c7df3d95decee344 Mon Sep 17 00:00:00 2001
From: "Bradley M. Small" <bradley_small@hotmail.com>
Date: Thu, 27 Feb 2020 21:02:16 -0500
Subject: [PATCH] Adding common-lisp work

---
 common-lisp/anagram/README.md                 |  61 +++
 common-lisp/anagram/anagram-test.lisp         |  54 +++
 common-lisp/anagram/anagram.lisp              |  18 +
 common-lisp/beer-song/.#beer-song.lisp        |   1 +
 common-lisp/beer-song/README.md               | 375 ++++++++++++++++++
 common-lisp/beer-song/beer-song-test.lisp     |  65 +++
 common-lisp/beer-song/beer-song.lisp          |  29 ++
 common-lisp/hamming/README.md                 |  78 ++++
 common-lisp/hamming/hamming-test.lisp         |  32 ++
 common-lisp/hamming/hamming.lisp              |  12 +
 common-lisp/hello-world/README.md             |  69 ++++
 common-lisp/hello-world/hello-world-test.lisp |  20 +
 common-lisp/hello-world/hello-world.lisp      |   9 +
 common-lisp/leap/README.md                    |  78 ++++
 common-lisp/leap/leap-test.lisp               |  27 ++
 common-lisp/leap/leap.lisp                    |  10 +
 common-lisp/leap/testme.lisp                  |  17 +
 common-lisp/rna-transcription/README.md       |  73 ++++
 .../rna-transcription-test.lisp               |  30 ++
 .../rna-transcription/rna-transcription.lisp  |  14 +
 common-lisp/two-fer/README.md                 |  80 ++++
 common-lisp/two-fer/two-fer-test.lisp         |  40 ++
 common-lisp/two-fer/two-fer.lisp              |  12 +
 23 files changed, 1204 insertions(+)
 create mode 100644 common-lisp/anagram/README.md
 create mode 100644 common-lisp/anagram/anagram-test.lisp
 create mode 100644 common-lisp/anagram/anagram.lisp
 create mode 120000 common-lisp/beer-song/.#beer-song.lisp
 create mode 100644 common-lisp/beer-song/README.md
 create mode 100644 common-lisp/beer-song/beer-song-test.lisp
 create mode 100644 common-lisp/beer-song/beer-song.lisp
 create mode 100644 common-lisp/hamming/README.md
 create mode 100644 common-lisp/hamming/hamming-test.lisp
 create mode 100644 common-lisp/hamming/hamming.lisp
 create mode 100644 common-lisp/hello-world/README.md
 create mode 100644 common-lisp/hello-world/hello-world-test.lisp
 create mode 100644 common-lisp/hello-world/hello-world.lisp
 create mode 100644 common-lisp/leap/README.md
 create mode 100644 common-lisp/leap/leap-test.lisp
 create mode 100644 common-lisp/leap/leap.lisp
 create mode 100644 common-lisp/leap/testme.lisp
 create mode 100644 common-lisp/rna-transcription/README.md
 create mode 100644 common-lisp/rna-transcription/rna-transcription-test.lisp
 create mode 100644 common-lisp/rna-transcription/rna-transcription.lisp
 create mode 100644 common-lisp/two-fer/README.md
 create mode 100644 common-lisp/two-fer/two-fer-test.lisp
 create mode 100644 common-lisp/two-fer/two-fer.lisp

diff --git a/common-lisp/anagram/README.md b/common-lisp/anagram/README.md
new file mode 100644
index 0000000..2f80c49
--- /dev/null
+++ b/common-lisp/anagram/README.md
@@ -0,0 +1,61 @@
+# Anagram
+
+Given a word and a list of possible anagrams, select the correct sublist.
+
+Given `"listen"` and a list of candidates like `"enlists" "google"
+"inlets" "banana"` the program should return a list containing
+`"inlets"`.
+
+## Setup
+
+Check out [Installing Common
+Lisp](https://exercism.io/tracks/common-lisp/installation) for
+instructions to get started or take a look at the guides available in
+the [track's side bar](https://exercism.io/my/tracks/common-lisp).
+
+## Formatting
+
+While Common Lisp doesn't care about indentation and layout of code,
+nor whether you use spaces or tabs, this is an important consideration
+for submissions to exercism.io. Excercism.io's code widget cannot
+handle mixing of tab and space characters well so using only spaces is recommended to make
+the code more readable to the human reviewers. Please review your
+editors settings on how to accomplish this. Below are instructions for
+popular editors for Common Lisp.
+
+### VIM
+
+Use the following commands to ensure VIM uses only spaces for
+indentation:
+
+```vimscript
+:set tabstop=2
+:set shiftwidth=2
+:set expandtab
+```
+
+(or as a oneliner `:set tabstop=2 shiftwidth=2 expandtab`). This can
+be added to your `~/.vimrc` file to use it all the time.
+
+### Emacs
+
+Emacs is very well suited for editing Common Lisp and has many
+powerful add-on packages available. The only thing that one needs to
+do with a stock emacs to make it work well with exercism.io is to
+evaluate the following code:
+
+`(setq-default indent-tabs-mode nil)`
+
+This can be placed in your `~/.emacs` (or `~/.emacs.d/init.el`) in
+order to have it set whenever Emacs is launched.
+
+One suggested add-on for Emacs and Common Lisp is
+[SLIME](https://github.com/slime/slime) which offers tight integration
+with the REPL; making iterative coding and testing very easy.
+
+## Source
+
+Inspired by the Extreme Startup game [https://github.com/rchatley/extreme_startup](https://github.com/rchatley/extreme_startup)
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
diff --git a/common-lisp/anagram/anagram-test.lisp b/common-lisp/anagram/anagram-test.lisp
new file mode 100644
index 0000000..73678fb
--- /dev/null
+++ b/common-lisp/anagram/anagram-test.lisp
@@ -0,0 +1,54 @@
+(ql:quickload "lisp-unit")
+#-xlisp-test (load "anagram")
+
+(defpackage #:anagram-test
+  (:use #:common-lisp #:lisp-unit))
+
+(in-package #:anagram-test)
+
+(define-test no-matches
+  (assert-equal '()
+      (anagram:anagrams-for
+       "diaper"
+       '("hello" "world" "zombies" "pants"))))
+
+(define-test detect-simple-anagram
+  (assert-equal '("tan")
+      (anagram:anagrams-for "ant" '("tan" "stand" "at"))))
+
+(define-test does-not-confuse-different-duplicates
+  (assert-equal '() (anagram:anagrams-for "galea" '("eagle"))))
+
+(define-test eliminate-anagram-subsets
+  (assert-equal '() (anagram:anagrams-for "good" '("dog" "goody"))))
+
+(define-test detect-anagram
+  (assert-equal '("inlets")
+      (anagram:anagrams-for
+       "listen"
+       '("enlists" "google" "inlets" "banana"))))
+
+(define-test multiple-anagrams
+  (assert-equal '("gallery" "regally" "largely")
+      (anagram:anagrams-for
+       "allergy"
+       '("gallery" "ballerina" "regally" "clergy" "largely" "leading"))))
+
+(define-test case-insensitive-anagrams
+  (assert-equal '("Carthorse")
+      (anagram:anagrams-for
+       "Orchestra"
+       '("cashregister" "Carthorse" "radishes"))))
+
+(define-test word-is-not-own-anagram
+  (assert-equal '()
+      (anagram:anagrams-for "banana" '("banana"))))
+
+(define-test word-is-not-own-anagram-case-insensitively
+  (assert-equal '()
+      (anagram:anagrams-for "bananarama" '("BananaRama"))))
+
+#-xlisp-test
+(let ((*print-errors* t)
+      (*print-failures* t))
+  (run-tests :all :anagram-test))
diff --git a/common-lisp/anagram/anagram.lisp b/common-lisp/anagram/anagram.lisp
new file mode 100644
index 0000000..e8c4a42
--- /dev/null
+++ b/common-lisp/anagram/anagram.lisp
@@ -0,0 +1,18 @@
+;;(in-package #:cl-user)
+
+(defpackage #:anagram
+  (:use #:common-lisp)
+  (:export #:anagrams-for))
+
+(in-package #:anagram)
+
+(defun anagrams-for (str list-arg)
+  "anagrams-for takes a string and a list and returns a list of its anagrams."
+  (flet ((make-comparable (word)
+           (sort (copy-seq word) #'string-lessp)))
+    (loop :with presorted-str = (make-comparable str) 
+      :for word :in list-arg
+          :when (and (string-not-equal str word)
+                     (string-equal (make-comparable word)
+                                   presorted-str))
+            :collect  word)))
diff --git a/common-lisp/beer-song/.#beer-song.lisp b/common-lisp/beer-song/.#beer-song.lisp
new file mode 120000
index 0000000..2069bc6
--- /dev/null
+++ b/common-lisp/beer-song/.#beer-song.lisp
@@ -0,0 +1 @@
+bms@bmsLaptop.30080:1581721011
\ No newline at end of file
diff --git a/common-lisp/beer-song/README.md b/common-lisp/beer-song/README.md
new file mode 100644
index 0000000..0eeaf49
--- /dev/null
+++ b/common-lisp/beer-song/README.md
@@ -0,0 +1,375 @@
+# Beer Song
+
+Recite the lyrics to that beloved classic, that field-trip favorite: 99 Bottles of Beer on the Wall.
+
+Note that not all verses are identical.
+
+```text
+99 bottles of beer on the wall, 99 bottles of beer.
+Take one down and pass it around, 98 bottles of beer on the wall.
+
+98 bottles of beer on the wall, 98 bottles of beer.
+Take one down and pass it around, 97 bottles of beer on the wall.
+
+97 bottles of beer on the wall, 97 bottles of beer.
+Take one down and pass it around, 96 bottles of beer on the wall.
+
+96 bottles of beer on the wall, 96 bottles of beer.
+Take one down and pass it around, 95 bottles of beer on the wall.
+
+95 bottles of beer on the wall, 95 bottles of beer.
+Take one down and pass it around, 94 bottles of beer on the wall.
+
+94 bottles of beer on the wall, 94 bottles of beer.
+Take one down and pass it around, 93 bottles of beer on the wall.
+
+93 bottles of beer on the wall, 93 bottles of beer.
+Take one down and pass it around, 92 bottles of beer on the wall.
+
+92 bottles of beer on the wall, 92 bottles of beer.
+Take one down and pass it around, 91 bottles of beer on the wall.
+
+91 bottles of beer on the wall, 91 bottles of beer.
+Take one down and pass it around, 90 bottles of beer on the wall.
+
+90 bottles of beer on the wall, 90 bottles of beer.
+Take one down and pass it around, 89 bottles of beer on the wall.
+
+89 bottles of beer on the wall, 89 bottles of beer.
+Take one down and pass it around, 88 bottles of beer on the wall.
+
+88 bottles of beer on the wall, 88 bottles of beer.
+Take one down and pass it around, 87 bottles of beer on the wall.
+
+87 bottles of beer on the wall, 87 bottles of beer.
+Take one down and pass it around, 86 bottles of beer on the wall.
+
+86 bottles of beer on the wall, 86 bottles of beer.
+Take one down and pass it around, 85 bottles of beer on the wall.
+
+85 bottles of beer on the wall, 85 bottles of beer.
+Take one down and pass it around, 84 bottles of beer on the wall.
+
+84 bottles of beer on the wall, 84 bottles of beer.
+Take one down and pass it around, 83 bottles of beer on the wall.
+
+83 bottles of beer on the wall, 83 bottles of beer.
+Take one down and pass it around, 82 bottles of beer on the wall.
+
+82 bottles of beer on the wall, 82 bottles of beer.
+Take one down and pass it around, 81 bottles of beer on the wall.
+
+81 bottles of beer on the wall, 81 bottles of beer.
+Take one down and pass it around, 80 bottles of beer on the wall.
+
+80 bottles of beer on the wall, 80 bottles of beer.
+Take one down and pass it around, 79 bottles of beer on the wall.
+
+79 bottles of beer on the wall, 79 bottles of beer.
+Take one down and pass it around, 78 bottles of beer on the wall.
+
+78 bottles of beer on the wall, 78 bottles of beer.
+Take one down and pass it around, 77 bottles of beer on the wall.
+
+77 bottles of beer on the wall, 77 bottles of beer.
+Take one down and pass it around, 76 bottles of beer on the wall.
+
+76 bottles of beer on the wall, 76 bottles of beer.
+Take one down and pass it around, 75 bottles of beer on the wall.
+
+75 bottles of beer on the wall, 75 bottles of beer.
+Take one down and pass it around, 74 bottles of beer on the wall.
+
+74 bottles of beer on the wall, 74 bottles of beer.
+Take one down and pass it around, 73 bottles of beer on the wall.
+
+73 bottles of beer on the wall, 73 bottles of beer.
+Take one down and pass it around, 72 bottles of beer on the wall.
+
+72 bottles of beer on the wall, 72 bottles of beer.
+Take one down and pass it around, 71 bottles of beer on the wall.
+
+71 bottles of beer on the wall, 71 bottles of beer.
+Take one down and pass it around, 70 bottles of beer on the wall.
+
+70 bottles of beer on the wall, 70 bottles of beer.
+Take one down and pass it around, 69 bottles of beer on the wall.
+
+69 bottles of beer on the wall, 69 bottles of beer.
+Take one down and pass it around, 68 bottles of beer on the wall.
+
+68 bottles of beer on the wall, 68 bottles of beer.
+Take one down and pass it around, 67 bottles of beer on the wall.
+
+67 bottles of beer on the wall, 67 bottles of beer.
+Take one down and pass it around, 66 bottles of beer on the wall.
+
+66 bottles of beer on the wall, 66 bottles of beer.
+Take one down and pass it around, 65 bottles of beer on the wall.
+
+65 bottles of beer on the wall, 65 bottles of beer.
+Take one down and pass it around, 64 bottles of beer on the wall.
+
+64 bottles of beer on the wall, 64 bottles of beer.
+Take one down and pass it around, 63 bottles of beer on the wall.
+
+63 bottles of beer on the wall, 63 bottles of beer.
+Take one down and pass it around, 62 bottles of beer on the wall.
+
+62 bottles of beer on the wall, 62 bottles of beer.
+Take one down and pass it around, 61 bottles of beer on the wall.
+
+61 bottles of beer on the wall, 61 bottles of beer.
+Take one down and pass it around, 60 bottles of beer on the wall.
+
+60 bottles of beer on the wall, 60 bottles of beer.
+Take one down and pass it around, 59 bottles of beer on the wall.
+
+59 bottles of beer on the wall, 59 bottles of beer.
+Take one down and pass it around, 58 bottles of beer on the wall.
+
+58 bottles of beer on the wall, 58 bottles of beer.
+Take one down and pass it around, 57 bottles of beer on the wall.
+
+57 bottles of beer on the wall, 57 bottles of beer.
+Take one down and pass it around, 56 bottles of beer on the wall.
+
+56 bottles of beer on the wall, 56 bottles of beer.
+Take one down and pass it around, 55 bottles of beer on the wall.
+
+55 bottles of beer on the wall, 55 bottles of beer.
+Take one down and pass it around, 54 bottles of beer on the wall.
+
+54 bottles of beer on the wall, 54 bottles of beer.
+Take one down and pass it around, 53 bottles of beer on the wall.
+
+53 bottles of beer on the wall, 53 bottles of beer.
+Take one down and pass it around, 52 bottles of beer on the wall.
+
+52 bottles of beer on the wall, 52 bottles of beer.
+Take one down and pass it around, 51 bottles of beer on the wall.
+
+51 bottles of beer on the wall, 51 bottles of beer.
+Take one down and pass it around, 50 bottles of beer on the wall.
+
+50 bottles of beer on the wall, 50 bottles of beer.
+Take one down and pass it around, 49 bottles of beer on the wall.
+
+49 bottles of beer on the wall, 49 bottles of beer.
+Take one down and pass it around, 48 bottles of beer on the wall.
+
+48 bottles of beer on the wall, 48 bottles of beer.
+Take one down and pass it around, 47 bottles of beer on the wall.
+
+47 bottles of beer on the wall, 47 bottles of beer.
+Take one down and pass it around, 46 bottles of beer on the wall.
+
+46 bottles of beer on the wall, 46 bottles of beer.
+Take one down and pass it around, 45 bottles of beer on the wall.
+
+45 bottles of beer on the wall, 45 bottles of beer.
+Take one down and pass it around, 44 bottles of beer on the wall.
+
+44 bottles of beer on the wall, 44 bottles of beer.
+Take one down and pass it around, 43 bottles of beer on the wall.
+
+43 bottles of beer on the wall, 43 bottles of beer.
+Take one down and pass it around, 42 bottles of beer on the wall.
+
+42 bottles of beer on the wall, 42 bottles of beer.
+Take one down and pass it around, 41 bottles of beer on the wall.
+
+41 bottles of beer on the wall, 41 bottles of beer.
+Take one down and pass it around, 40 bottles of beer on the wall.
+
+40 bottles of beer on the wall, 40 bottles of beer.
+Take one down and pass it around, 39 bottles of beer on the wall.
+
+39 bottles of beer on the wall, 39 bottles of beer.
+Take one down and pass it around, 38 bottles of beer on the wall.
+
+38 bottles of beer on the wall, 38 bottles of beer.
+Take one down and pass it around, 37 bottles of beer on the wall.
+
+37 bottles of beer on the wall, 37 bottles of beer.
+Take one down and pass it around, 36 bottles of beer on the wall.
+
+36 bottles of beer on the wall, 36 bottles of beer.
+Take one down and pass it around, 35 bottles of beer on the wall.
+
+35 bottles of beer on the wall, 35 bottles of beer.
+Take one down and pass it around, 34 bottles of beer on the wall.
+
+34 bottles of beer on the wall, 34 bottles of beer.
+Take one down and pass it around, 33 bottles of beer on the wall.
+
+33 bottles of beer on the wall, 33 bottles of beer.
+Take one down and pass it around, 32 bottles of beer on the wall.
+
+32 bottles of beer on the wall, 32 bottles of beer.
+Take one down and pass it around, 31 bottles of beer on the wall.
+
+31 bottles of beer on the wall, 31 bottles of beer.
+Take one down and pass it around, 30 bottles of beer on the wall.
+
+30 bottles of beer on the wall, 30 bottles of beer.
+Take one down and pass it around, 29 bottles of beer on the wall.
+
+29 bottles of beer on the wall, 29 bottles of beer.
+Take one down and pass it around, 28 bottles of beer on the wall.
+
+28 bottles of beer on the wall, 28 bottles of beer.
+Take one down and pass it around, 27 bottles of beer on the wall.
+
+27 bottles of beer on the wall, 27 bottles of beer.
+Take one down and pass it around, 26 bottles of beer on the wall.
+
+26 bottles of beer on the wall, 26 bottles of beer.
+Take one down and pass it around, 25 bottles of beer on the wall.
+
+25 bottles of beer on the wall, 25 bottles of beer.
+Take one down and pass it around, 24 bottles of beer on the wall.
+
+24 bottles of beer on the wall, 24 bottles of beer.
+Take one down and pass it around, 23 bottles of beer on the wall.
+
+23 bottles of beer on the wall, 23 bottles of beer.
+Take one down and pass it around, 22 bottles of beer on the wall.
+
+22 bottles of beer on the wall, 22 bottles of beer.
+Take one down and pass it around, 21 bottles of beer on the wall.
+
+21 bottles of beer on the wall, 21 bottles of beer.
+Take one down and pass it around, 20 bottles of beer on the wall.
+
+20 bottles of beer on the wall, 20 bottles of beer.
+Take one down and pass it around, 19 bottles of beer on the wall.
+
+19 bottles of beer on the wall, 19 bottles of beer.
+Take one down and pass it around, 18 bottles of beer on the wall.
+
+18 bottles of beer on the wall, 18 bottles of beer.
+Take one down and pass it around, 17 bottles of beer on the wall.
+
+17 bottles of beer on the wall, 17 bottles of beer.
+Take one down and pass it around, 16 bottles of beer on the wall.
+
+16 bottles of beer on the wall, 16 bottles of beer.
+Take one down and pass it around, 15 bottles of beer on the wall.
+
+15 bottles of beer on the wall, 15 bottles of beer.
+Take one down and pass it around, 14 bottles of beer on the wall.
+
+14 bottles of beer on the wall, 14 bottles of beer.
+Take one down and pass it around, 13 bottles of beer on the wall.
+
+13 bottles of beer on the wall, 13 bottles of beer.
+Take one down and pass it around, 12 bottles of beer on the wall.
+
+12 bottles of beer on the wall, 12 bottles of beer.
+Take one down and pass it around, 11 bottles of beer on the wall.
+
+11 bottles of beer on the wall, 11 bottles of beer.
+Take one down and pass it around, 10 bottles of beer on the wall.
+
+10 bottles of beer on the wall, 10 bottles of beer.
+Take one down and pass it around, 9 bottles of beer on the wall.
+
+9 bottles of beer on the wall, 9 bottles of beer.
+Take one down and pass it around, 8 bottles of beer on the wall.
+
+8 bottles of beer on the wall, 8 bottles of beer.
+Take one down and pass it around, 7 bottles of beer on the wall.
+
+7 bottles of beer on the wall, 7 bottles of beer.
+Take one down and pass it around, 6 bottles of beer on the wall.
+
+6 bottles of beer on the wall, 6 bottles of beer.
+Take one down and pass it around, 5 bottles of beer on the wall.
+
+5 bottles of beer on the wall, 5 bottles of beer.
+Take one down and pass it around, 4 bottles of beer on the wall.
+
+4 bottles of beer on the wall, 4 bottles of beer.
+Take one down and pass it around, 3 bottles of beer on the wall.
+
+3 bottles of beer on the wall, 3 bottles of beer.
+Take one down and pass it around, 2 bottles of beer on the wall.
+
+2 bottles of beer on the wall, 2 bottles of beer.
+Take one down and pass it around, 1 bottle of beer on the wall.
+
+1 bottle of beer on the wall, 1 bottle of beer.
+Take it down and pass it around, no more bottles of beer on the wall.
+
+No more bottles of beer on the wall, no more bottles of beer.
+Go to the store and buy some more, 99 bottles of beer on the wall.
+```
+
+## For bonus points
+
+Did you get the tests passing and the code clean? If you want to, these
+are some additional things you could try:
+
+* Remove as much duplication as you possibly can.
+* Optimize for readability, even if it means introducing duplication.
+* If you've removed all the duplication, do you have a lot of
+  conditionals? Try replacing the conditionals with polymorphism, if it
+  applies in this language. How readable is it?
+
+Then please share your thoughts in a comment on the submission. Did this
+experiment make the code better? Worse? Did you learn anything from it?
+
+## Setup
+
+Check out [Installing Common
+Lisp](https://exercism.io/tracks/common-lisp/installation) for
+instructions to get started or take a look at the guides available in
+the [track's side bar](https://exercism.io/my/tracks/common-lisp).
+
+## Formatting
+
+While Common Lisp doesn't care about indentation and layout of code,
+nor whether you use spaces or tabs, this is an important consideration
+for submissions to exercism.io. Excercism.io's code widget cannot
+handle mixing of tab and space characters well so using only spaces is recommended to make
+the code more readable to the human reviewers. Please review your
+editors settings on how to accomplish this. Below are instructions for
+popular editors for Common Lisp.
+
+### VIM
+
+Use the following commands to ensure VIM uses only spaces for
+indentation:
+
+```vimscript
+:set tabstop=2
+:set shiftwidth=2
+:set expandtab
+```
+
+(or as a oneliner `:set tabstop=2 shiftwidth=2 expandtab`). This can
+be added to your `~/.vimrc` file to use it all the time.
+
+### Emacs
+
+Emacs is very well suited for editing Common Lisp and has many
+powerful add-on packages available. The only thing that one needs to
+do with a stock emacs to make it work well with exercism.io is to
+evaluate the following code:
+
+`(setq-default indent-tabs-mode nil)`
+
+This can be placed in your `~/.emacs` (or `~/.emacs.d/init.el`) in
+order to have it set whenever Emacs is launched.
+
+One suggested add-on for Emacs and Common Lisp is
+[SLIME](https://github.com/slime/slime) which offers tight integration
+with the REPL; making iterative coding and testing very easy.
+
+## Source
+
+Learn to Program by Chris Pine [http://pine.fm/LearnToProgram/?Chapter=06](http://pine.fm/LearnToProgram/?Chapter=06)
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
diff --git a/common-lisp/beer-song/beer-song-test.lisp b/common-lisp/beer-song/beer-song-test.lisp
new file mode 100644
index 0000000..9ddb753
--- /dev/null
+++ b/common-lisp/beer-song/beer-song-test.lisp
@@ -0,0 +1,65 @@
+(ql:quickload "lisp-unit")
+#-xlisp-test (load "beer-song")
+
+(defpackage #:beer-song-test
+  (:use #:common-lisp #:lisp-unit))
+
+(in-package #:beer-song-test)
+
+(defparameter +verse-8+
+  (format nil
+          "8 bottles of beer on the wall, 8 bottles of beer.~&~
+           Take one down and pass it around, 7 bottles of beer on the wall.~&"))
+(defparameter +verse-2+
+  (format nil
+          "2 bottles of beer on the wall, 2 bottles of beer.~&~
+           Take one down and pass it around, 1 bottle of beer on the wall.~&"))
+(defparameter +verse-1+
+  (format nil
+          "1 bottle of beer on the wall, 1 bottle of beer.~&~
+           Take it down and pass it around, no more bottles of beer on the wall.~&"))
+(defparameter +verse-0+
+  (format nil
+          "No more bottles of beer on the wall, no more bottles of beer.~&~
+           Go to the store and buy some more, 99 bottles of beer on the wall.~&"))
+
+(defparameter +song-8-6+
+  (format nil
+          "8 bottles of beer on the wall, 8 bottles of beer.~&~
+           Take one down and pass it around, 7 bottles of beer on the wall.~&~
+           ~%~
+           7 bottles of beer on the wall, 7 bottles of beer.~&~
+           Take one down and pass it around, 6 bottles of beer on the wall.~&~
+           ~%~
+           6 bottles of beer on the wall, 6 bottles of beer.~&~
+           Take one down and pass it around, 5 bottles of beer on the wall.~&~
+           ~%"))
+(defparameter +song-3-0+
+  (format nil
+          "3 bottles of beer on the wall, 3 bottles of beer.~&~
+           Take one down and pass it around, 2 bottles of beer on the wall.~&~
+           ~%~
+           2 bottles of beer on the wall, 2 bottles of beer.~&~
+           Take one down and pass it around, 1 bottle of beer on the wall.~&~
+           ~%~
+           1 bottle of beer on the wall, 1 bottle of beer.~&~
+           Take it down and pass it around, no more bottles of beer on the wall.~&~
+           ~%~
+           No more bottles of beer on the wall, no more bottles of beer.~&~
+           Go to the store and buy some more, 99 bottles of beer on the wall.~&~
+           ~%"))
+
+(define-test test-verse
+  (assert-equal +verse-8+ (beer:verse 8))
+  (assert-equal +verse-2+ (beer:verse 2))
+  (assert-equal +verse-1+ (beer:verse 1)))
+
+(define-test test-song
+  (assert-equal +song-8-6+ (beer:sing 8 6))
+  (assert-equal +song-3-0+ (beer:sing 3)))
+
+
+#-xlisp-test
+(let ((*print-errors* t)
+      (*print-failures* t))
+  (run-tests :all :beer-song-test))
diff --git a/common-lisp/beer-song/beer-song.lisp b/common-lisp/beer-song/beer-song.lisp
new file mode 100644
index 0000000..b69a329
--- /dev/null
+++ b/common-lisp/beer-song/beer-song.lisp
@@ -0,0 +1,29 @@
+(in-package #:cl-user)
+(defpackage #:beer
+  (:use #:common-lisp)
+  (:export #:verse #:sing))
+
+(in-package #:beer)
+
+(defun verse (beer-verse)
+  "verse returns a single verse of the beer song."
+  (cond
+    ((= beer-verse 0)
+      (format nil "No more bottles of beer on the wall, no more bottles of beer.~&~
+        Go to the store and buy some more, 99 bottles of beer on the wall.~%"))
+    ((= beer-verse 1)
+      (format nil "1 bottle of beer on the wall, 1 bottle of beer.~&~
+        Take it down and pass it around, no more bottles of beer on the wall.~%"))
+    ((= beer-verse 2)
+      (format nil "2 bottles of beer on the wall, 2 bottles of beer.~&~
+        Take one down and pass it around, 1 bottle of beer on the wall.~%"))
+    (t  
+      (format nil "~A bottles of beer on the wall, ~A bottles of beer.~&~
+        Take one down and pass it around, ~A bottles of beer on the wall.~%"
+              beer-verse beer-verse (- beer-verse 1)))))
+
+(defun sing (begin-verse &optional (end-verse 0))
+  "sing returns the beer song, from begin verse to the end verse"
+  (loop for beer-verse downfrom begin-verse to end-verse by 1
+        collect (verse beer-verse) into result finally (return (format nil "~{~A~%~}" result)))   
+  )
diff --git a/common-lisp/hamming/README.md b/common-lisp/hamming/README.md
new file mode 100644
index 0000000..4ab94a3
--- /dev/null
+++ b/common-lisp/hamming/README.md
@@ -0,0 +1,78 @@
+# Hamming
+
+Calculate the Hamming Distance between two DNA strands.
+
+Your body is made up of cells that contain DNA. Those cells regularly wear out and need replacing, which they achieve by dividing into daughter cells. In fact, the average human body experiences about 10 quadrillion cell divisions in a lifetime!
+
+When cells divide, their DNA replicates too. Sometimes during this process mistakes happen and single pieces of DNA get encoded with the incorrect information. If we compare two strands of DNA and count the differences between them we can see how many mistakes occurred. This is known as the "Hamming Distance".
+
+We read DNA using the letters C,A,G and T. Two strands might look like this:
+
+    GAGCCTACTAACGGGAT
+    CATCGTAATGACGGCCT
+    ^ ^ ^  ^ ^    ^^
+
+They have 7 differences, and therefore the Hamming Distance is 7.
+
+The Hamming Distance is useful for lots of things in science, not just biology, so it's a nice phrase to be familiar with :)
+
+# Implementation notes
+
+The Hamming distance is only defined for sequences of equal length, so
+an attempt to calculate it between sequences of different lengths should
+not work. The general handling of this situation (e.g., raising an
+exception vs returning a special value) may differ between languages.
+
+## Setup
+
+Check out [Installing Common
+Lisp](https://exercism.io/tracks/common-lisp/installation) for
+instructions to get started or take a look at the guides available in
+the [track's side bar](https://exercism.io/my/tracks/common-lisp).
+
+## Formatting
+
+While Common Lisp doesn't care about indentation and layout of code,
+nor whether you use spaces or tabs, this is an important consideration
+for submissions to exercism.io. Excercism.io's code widget cannot
+handle mixing of tab and space characters well so using only spaces is recommended to make
+the code more readable to the human reviewers. Please review your
+editors settings on how to accomplish this. Below are instructions for
+popular editors for Common Lisp.
+
+### VIM
+
+Use the following commands to ensure VIM uses only spaces for
+indentation:
+
+```vimscript
+:set tabstop=2
+:set shiftwidth=2
+:set expandtab
+```
+
+(or as a oneliner `:set tabstop=2 shiftwidth=2 expandtab`). This can
+be added to your `~/.vimrc` file to use it all the time.
+
+### Emacs
+
+Emacs is very well suited for editing Common Lisp and has many
+powerful add-on packages available. The only thing that one needs to
+do with a stock emacs to make it work well with exercism.io is to
+evaluate the following code:
+
+`(setq-default indent-tabs-mode nil)`
+
+This can be placed in your `~/.emacs` (or `~/.emacs.d/init.el`) in
+order to have it set whenever Emacs is launched.
+
+One suggested add-on for Emacs and Common Lisp is
+[SLIME](https://github.com/slime/slime) which offers tight integration
+with the REPL; making iterative coding and testing very easy.
+
+## Source
+
+The Calculating Point Mutations problem at Rosalind [http://rosalind.info/problems/hamm/](http://rosalind.info/problems/hamm/)
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
diff --git a/common-lisp/hamming/hamming-test.lisp b/common-lisp/hamming/hamming-test.lisp
new file mode 100644
index 0000000..57ddf79
--- /dev/null
+++ b/common-lisp/hamming/hamming-test.lisp
@@ -0,0 +1,32 @@
+(ql:quickload "lisp-unit")
+#-xlisp-test (load "hamming")
+
+(defpackage #:hamming-test
+  (:use #:common-lisp #:lisp-unit))
+
+(in-package #:hamming-test)
+
+(define-test no-difference-between-empty-strands
+  (assert-equal 0 (hamming:distance "" "")))
+
+(define-test no-difference-between-identical-strands
+  (assert-equal 0 (hamming:distance "GGACTGA" "GGACTGA")))
+
+(define-test complete-hamming-distance-in-small-strand
+  (assert-equal 3 (hamming:distance "ACT" "GGA")))
+
+(define-test small-hamming-distance-in-middle-somewhere
+  (assert-equal 1 (hamming:distance "GGACG" "GGTCG")))
+
+(define-test larger-distance
+  (assert-equal 2 (hamming:distance "ACCAGGG" "ACTATGG")))
+
+(define-test invalid-to-get-distance-for-different-length-strings
+  (assert-equal nil (hamming:distance "AGACAACAGCCAGCCGCCGGATT" "AGGCAA"))
+  (assert-equal nil (hamming:distance "AGACAACAGCCAGCCGCCGGATT" "AGACATCTTTCAGCCGCCGGATTAGGCAA"))
+  (assert-equal nil (hamming:distance "AGG" "AGACAACAGCCAGCCGCCGGATT")))
+
+#-xlisp-test
+(let ((*print-errors* t)
+      (*print-failures* t))
+  (run-tests :all :hamming-test))
diff --git a/common-lisp/hamming/hamming.lisp b/common-lisp/hamming/hamming.lisp
new file mode 100644
index 0000000..59428ea
--- /dev/null
+++ b/common-lisp/hamming/hamming.lisp
@@ -0,0 +1,12 @@
+(defpackage #:hamming
+  (:use #:cl)
+  (:export #:distance))
+
+(in-package #:hamming)
+
+(defun distance (dna1 dna2)
+  "Number of positional differences in two equal length dna strands."
+  (when (= (length dna1) (length dna2)) 
+    (loop :for x :across dna1
+          :for y :across dna2
+          :count (char/= x y))))
diff --git a/common-lisp/hello-world/README.md b/common-lisp/hello-world/README.md
new file mode 100644
index 0000000..a563e48
--- /dev/null
+++ b/common-lisp/hello-world/README.md
@@ -0,0 +1,69 @@
+# Hello World
+
+The classical introductory exercise. Just say "Hello, World!".
+
+["Hello, World!"](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program) is
+the traditional first program for beginning programming in a new language
+or environment.
+
+The objectives are simple:
+
+- Write a function that returns the string "Hello, World!".
+- Run the test suite and make sure that it succeeds.
+- Submit your solution and check it at the website.
+
+If everything goes well, you will be ready to fetch your first real exercise.
+
+## Setup
+
+Check out [Installing Common
+Lisp](https://exercism.io/tracks/common-lisp/installation) for
+instructions to get started or take a look at the guides available in
+the [track's side bar](https://exercism.io/my/tracks/common-lisp).
+
+## Formatting
+
+While Common Lisp doesn't care about indentation and layout of code,
+nor whether you use spaces or tabs, this is an important consideration
+for submissions to exercism.io. Excercism.io's code widget cannot
+handle mixing of tab and space characters well so using only spaces is recommended to make
+the code more readable to the human reviewers. Please review your
+editors settings on how to accomplish this. Below are instructions for
+popular editors for Common Lisp.
+
+### VIM
+
+Use the following commands to ensure VIM uses only spaces for
+indentation:
+
+```vimscript
+:set tabstop=2
+:set shiftwidth=2
+:set expandtab
+```
+
+(or as a oneliner `:set tabstop=2 shiftwidth=2 expandtab`). This can
+be added to your `~/.vimrc` file to use it all the time.
+
+### Emacs
+
+Emacs is very well suited for editing Common Lisp and has many
+powerful add-on packages available. The only thing that one needs to
+do with a stock emacs to make it work well with exercism.io is to
+evaluate the following code:
+
+`(setq-default indent-tabs-mode nil)`
+
+This can be placed in your `~/.emacs` (or `~/.emacs.d/init.el`) in
+order to have it set whenever Emacs is launched.
+
+One suggested add-on for Emacs and Common Lisp is
+[SLIME](https://github.com/slime/slime) which offers tight integration
+with the REPL; making iterative coding and testing very easy.
+
+## Source
+
+This is an exercise to introduce users to using Exercism [http://en.wikipedia.org/wiki/%22Hello,_world!%22_program](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program)
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
diff --git a/common-lisp/hello-world/hello-world-test.lisp b/common-lisp/hello-world/hello-world-test.lisp
new file mode 100644
index 0000000..a7cad6a
--- /dev/null
+++ b/common-lisp/hello-world/hello-world-test.lisp
@@ -0,0 +1,20 @@
+;;; 
+;;; hello-world v1.1.0
+;;; 
+(ql:quickload "lisp-unit")
+#-xlisp-test (load "hello-world")
+
+(defpackage #:hello-world-test
+  (:use #:common-lisp #:lisp-unit))
+(in-package #:hello-world-test)
+
+(define-test
+  say-hi!
+  (assert-equal
+    "Hello, World!"
+    (hello-world:hello)))
+
+#-xlisp-test
+(let ((*print-errors* t)
+      (*print-failures* t))
+  (run-tests :all))
diff --git a/common-lisp/hello-world/hello-world.lisp b/common-lisp/hello-world/hello-world.lisp
new file mode 100644
index 0000000..ece6c4c
--- /dev/null
+++ b/common-lisp/hello-world/hello-world.lisp
@@ -0,0 +1,9 @@
+(in-package #:cl-user)
+(defpackage #:hello-world
+  (:use #:cl)
+  (:export #:hello))
+(in-package #:hello-world)
+
+(defun hello ()
+  "Hello, World!"
+)
diff --git a/common-lisp/leap/README.md b/common-lisp/leap/README.md
new file mode 100644
index 0000000..ec3bde8
--- /dev/null
+++ b/common-lisp/leap/README.md
@@ -0,0 +1,78 @@
+# Leap
+
+Given a year, report if it is a leap year.
+
+The tricky thing here is that a leap year in the Gregorian calendar occurs:
+
+```text
+on every year that is evenly divisible by 4
+  except every year that is evenly divisible by 100
+    unless the year is also evenly divisible by 400
+```
+
+For example, 1997 is not a leap year, but 1996 is.  1900 is not a leap
+year, but 2000 is.
+
+## Notes
+
+Though our exercise adopts some very simple rules, there is more to
+learn!
+
+For a delightful, four minute explanation of the whole leap year
+phenomenon, go watch [this youtube video][video].
+
+[video]: http://www.youtube.com/watch?v=xX96xng7sAE
+
+## Setup
+
+Check out [Installing Common
+Lisp](https://exercism.io/tracks/common-lisp/installation) for
+instructions to get started or take a look at the guides available in
+the [track's side bar](https://exercism.io/my/tracks/common-lisp).
+
+## Formatting
+
+While Common Lisp doesn't care about indentation and layout of code,
+nor whether you use spaces or tabs, this is an important consideration
+for submissions to exercism.io. Excercism.io's code widget cannot
+handle mixing of tab and space characters well so using only spaces is recommended to make
+the code more readable to the human reviewers. Please review your
+editors settings on how to accomplish this. Below are instructions for
+popular editors for Common Lisp.
+
+### VIM
+
+Use the following commands to ensure VIM uses only spaces for
+indentation:
+
+```vimscript
+:set tabstop=2
+:set shiftwidth=2
+:set expandtab
+```
+
+(or as a oneliner `:set tabstop=2 shiftwidth=2 expandtab`). This can
+be added to your `~/.vimrc` file to use it all the time.
+
+### Emacs
+
+Emacs is very well suited for editing Common Lisp and has many
+powerful add-on packages available. The only thing that one needs to
+do with a stock emacs to make it work well with exercism.io is to
+evaluate the following code:
+
+`(setq-default indent-tabs-mode nil)`
+
+This can be placed in your `~/.emacs` (or `~/.emacs.d/init.el`) in
+order to have it set whenever Emacs is launched.
+
+One suggested add-on for Emacs and Common Lisp is
+[SLIME](https://github.com/slime/slime) which offers tight integration
+with the REPL; making iterative coding and testing very easy.
+
+## Source
+
+JavaRanch Cattle Drive, exercise 3 [http://www.javaranch.com/leap.jsp](http://www.javaranch.com/leap.jsp)
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
diff --git a/common-lisp/leap/leap-test.lisp b/common-lisp/leap/leap-test.lisp
new file mode 100644
index 0000000..00e2621
--- /dev/null
+++ b/common-lisp/leap/leap-test.lisp
@@ -0,0 +1,27 @@
+(ql:quickload "lisp-unit")
+#-xlisp-test (load "leap")
+
+(defpackage #:leap-test
+  (:use #:common-lisp #:lisp-unit))
+
+(in-package #:leap-test)
+
+(define-test vanilla-leap-year
+  (assert-true (leap:leap-year-p 1996)))
+
+(define-test any-old-year
+  (assert-false (leap:leap-year-p 1997)))
+
+(define-test non-leap-even-year
+  (assert-false (leap:leap-year-p 1998)))
+
+(define-test century
+  (assert-false (leap:leap-year-p 1900)))
+
+(define-test exceptional-century
+  (assert-true (leap:leap-year-p 2400)))
+
+#-xlisp-test
+(let ((*print-errors* t)
+      (*print-failures* t))
+  (run-tests :all :leap-test))
diff --git a/common-lisp/leap/leap.lisp b/common-lisp/leap/leap.lisp
new file mode 100644
index 0000000..e79cf0b
--- /dev/null
+++ b/common-lisp/leap/leap.lisp
@@ -0,0 +1,10 @@
+(defpackage #:leap
+  (:use #:common-lisp)
+  (:export #:leap-year-p))
+(in-package #:leap)
+
+(defun leap-year-p (year)
+  (flet ((divis  (div) (zerop (mod year div)))
+         (ndivis (div) (not (zerop (mod year div)))))
+    (and (divis 4)
+         (or (ndivis 100) (divis 400)))))
diff --git a/common-lisp/leap/testme.lisp b/common-lisp/leap/testme.lisp
new file mode 100644
index 0000000..3a4be5a
--- /dev/null
+++ b/common-lisp/leap/testme.lisp
@@ -0,0 +1,17 @@
+(defvar proj-name)
+(defvar load-cmd)
+(defvar ut-cmd)
+
+(setq proj-name
+      (format  "%s" (file-name-sans-extension (file-name-nondirectory (buffer-file-name)))))
+(setq load-cmd
+  (format "(load \"%s\")" proj-name))
+(setq ut-cmd
+  (format "(lisp-unit::run-test :all  :%s)" proj-name))
+
+proj-name
+load-cmd
+ut-cmd
+
+(format "%s" (file-name-sans-extension (file-name-nondirectory (buffer-file-name))))
+
diff --git a/common-lisp/rna-transcription/README.md b/common-lisp/rna-transcription/README.md
new file mode 100644
index 0000000..e306ada
--- /dev/null
+++ b/common-lisp/rna-transcription/README.md
@@ -0,0 +1,73 @@
+# RNA Transcription
+
+Given a DNA strand, return its RNA complement (per RNA transcription).
+
+Both DNA and RNA strands are a sequence of nucleotides.
+
+The four nucleotides found in DNA are adenine (**A**), cytosine (**C**),
+guanine (**G**) and thymine (**T**).
+
+The four nucleotides found in RNA are adenine (**A**), cytosine (**C**),
+guanine (**G**) and uracil (**U**).
+
+Given a DNA strand, its transcribed RNA strand is formed by replacing
+each nucleotide with its complement:
+
+* `G` -> `C`
+* `C` -> `G`
+* `T` -> `A`
+* `A` -> `U`
+
+## Setup
+
+Check out [Installing Common
+Lisp](https://exercism.io/tracks/common-lisp/installation) for
+instructions to get started or take a look at the guides available in
+the [track's side bar](https://exercism.io/my/tracks/common-lisp).
+
+## Formatting
+
+While Common Lisp doesn't care about indentation and layout of code,
+nor whether you use spaces or tabs, this is an important consideration
+for submissions to exercism.io. Excercism.io's code widget cannot
+handle mixing of tab and space characters well so using only spaces is recommended to make
+the code more readable to the human reviewers. Please review your
+editors settings on how to accomplish this. Below are instructions for
+popular editors for Common Lisp.
+
+### VIM
+
+Use the following commands to ensure VIM uses only spaces for
+indentation:
+
+```vimscript
+:set tabstop=2
+:set shiftwidth=2
+:set expandtab
+```
+
+(or as a oneliner `:set tabstop=2 shiftwidth=2 expandtab`). This can
+be added to your `~/.vimrc` file to use it all the time.
+
+### Emacs
+
+Emacs is very well suited for editing Common Lisp and has many
+powerful add-on packages available. The only thing that one needs to
+do with a stock emacs to make it work well with exercism.io is to
+evaluate the following code:
+
+`(setq-default indent-tabs-mode nil)`
+
+This can be placed in your `~/.emacs` (or `~/.emacs.d/init.el`) in
+order to have it set whenever Emacs is launched.
+
+One suggested add-on for Emacs and Common Lisp is
+[SLIME](https://github.com/slime/slime) which offers tight integration
+with the REPL; making iterative coding and testing very easy.
+
+## Source
+
+Hyperphysics [http://hyperphysics.phy-astr.gsu.edu/hbase/Organic/transcription.html](http://hyperphysics.phy-astr.gsu.edu/hbase/Organic/transcription.html)
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
diff --git a/common-lisp/rna-transcription/rna-transcription-test.lisp b/common-lisp/rna-transcription/rna-transcription-test.lisp
new file mode 100644
index 0000000..daa68f8
--- /dev/null
+++ b/common-lisp/rna-transcription/rna-transcription-test.lisp
@@ -0,0 +1,30 @@
+(ql:quickload "lisp-unit")
+#-xlisp-test (load "rna-transcription")
+
+(defpackage :rna-transcription-test
+  (:use #:common-lisp #:lisp-unit))
+
+(in-package #:rna-transcription-test)
+
+(define-test transcribes-cytidine-to-guanosine
+  (assert-equal "G" (rna-transcription:to-rna "C")))
+
+(define-test transcribes-guanosine-to-cytidine
+  (assert-equal "C" (rna-transcription:to-rna "G")))
+
+(define-test transcribes-adenosine-to-uracile
+  (assert-equal "U" (rna-transcription:to-rna "A")))
+
+(define-test it-transcribes-thymidine-to-adenosine
+  (assert-equal "A" (rna-transcription:to-rna "T")))
+
+(define-test it-transcribes-all-nucleotides
+  (assert-equal "UGCACCAGAAUU" (rna-transcription:to-rna "ACGTGGTCTTAA")))
+
+(define-test it-validates-dna-strands
+  (assert-error 'error (rna-transcription:to-rna "XCGFGGTDTTAA")))
+
+#-xlisp-test
+(let ((*print-errors* t)
+      (*print-failures* t))
+  (run-tests :all :rna-transcription-test))
diff --git a/common-lisp/rna-transcription/rna-transcription.lisp b/common-lisp/rna-transcription/rna-transcription.lisp
new file mode 100644
index 0000000..4f245b7
--- /dev/null
+++ b/common-lisp/rna-transcription/rna-transcription.lisp
@@ -0,0 +1,14 @@
+(in-package #:cl-user)
+(defpackage #:rna-transcription
+  (:use #:cl)
+  (:export #:to-rna))
+(in-package #:rna-transcription)
+
+(defun to-rna (str)
+  "Transcribe a string representing DNA nucleotides to RNA."
+  (map 'string (lambda (c)
+                 (case c (#\G #\C)
+                         (#\C #\G)
+                         (#\T #\A)
+                         (#\A #\U)))
+       str))
diff --git a/common-lisp/two-fer/README.md b/common-lisp/two-fer/README.md
new file mode 100644
index 0000000..9650381
--- /dev/null
+++ b/common-lisp/two-fer/README.md
@@ -0,0 +1,80 @@
+# Two Fer
+
+`Two-fer` or `2-fer` is short for two for one. One for you and one for me.
+
+Given a name, return a string with the message:
+
+```text
+One for X, one for me.
+```
+
+Where X is the given name.
+
+However, if the name is missing, return the string:
+
+```text
+One for you, one for me.
+```
+
+Here are some examples:
+
+|Name    |String to return 
+|:-------|:------------------
+|Alice   |One for Alice, one for me. 
+|Bob     |One for Bob, one for me.
+|        |One for you, one for me.
+|Zaphod  |One for Zaphod, one for me.
+
+## Setup
+
+Check out [Installing Common
+Lisp](https://exercism.io/tracks/common-lisp/installation) for
+instructions to get started or take a look at the guides available in
+the [track's side bar](https://exercism.io/my/tracks/common-lisp).
+
+## Formatting
+
+While Common Lisp doesn't care about indentation and layout of code,
+nor whether you use spaces or tabs, this is an important consideration
+for submissions to exercism.io. Excercism.io's code widget cannot
+handle mixing of tab and space characters well so using only spaces is recommended to make
+the code more readable to the human reviewers. Please review your
+editors settings on how to accomplish this. Below are instructions for
+popular editors for Common Lisp.
+
+### VIM
+
+Use the following commands to ensure VIM uses only spaces for
+indentation:
+
+```vimscript
+:set tabstop=2
+:set shiftwidth=2
+:set expandtab
+```
+
+(or as a oneliner `:set tabstop=2 shiftwidth=2 expandtab`). This can
+be added to your `~/.vimrc` file to use it all the time.
+
+### Emacs
+
+Emacs is very well suited for editing Common Lisp and has many
+powerful add-on packages available. The only thing that one needs to
+do with a stock emacs to make it work well with exercism.io is to
+evaluate the following code:
+
+`(setq-default indent-tabs-mode nil)`
+
+This can be placed in your `~/.emacs` (or `~/.emacs.d/init.el`) in
+order to have it set whenever Emacs is launched.
+
+One suggested add-on for Emacs and Common Lisp is
+[SLIME](https://github.com/slime/slime) which offers tight integration
+with the REPL; making iterative coding and testing very easy.
+
+## Source
+
+[https://github.com/exercism/problem-specifications/issues/757](https://github.com/exercism/problem-specifications/issues/757)
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
diff --git a/common-lisp/two-fer/two-fer-test.lisp b/common-lisp/two-fer/two-fer-test.lisp
new file mode 100644
index 0000000..439b4dc
--- /dev/null
+++ b/common-lisp/two-fer/two-fer-test.lisp
@@ -0,0 +1,40 @@
+;;;
+;;; two-fer v1.2.0
+;;;
+(ql:quickload "lisp-unit")
+#-xlisp-test (load "two-fer")
+
+(defpackage #:two-fer-test
+  (:use #:common-lisp #:lisp-unit))
+(in-package #:two-fer-test)
+
+(define-test
+    no-name-given-nil
+    (assert-equal
+     "One for you, one for me."
+     (two-fer:twofer nil)))
+
+
+(define-test
+  a-name-given
+  (assert-equal
+    "One for Alice, one for me."
+    (two-fer:twofer "Alice")))
+
+
+(define-test
+    another-name-given
+    (assert-equal
+     "One for Bob, one for me."
+     (two-fer:twofer "Bob")))
+
+(define-test
+    no-name-given
+    (assert-equal
+     "One for you, one for me."
+     (two-fer:twofer)))
+
+#-xlisp-test
+(let ((*print-errors* t)
+      (*print-failures* t))
+  (run-tests :all))
diff --git a/common-lisp/two-fer/two-fer.lisp b/common-lisp/two-fer/two-fer.lisp
new file mode 100644
index 0000000..3be7583
--- /dev/null
+++ b/common-lisp/two-fer/two-fer.lisp
@@ -0,0 +1,12 @@
+(in-package #:cl-user)
+(defpackage #:two-fer
+  (:use #:cl)
+  (:export #:twofer))
+(in-package #:two-fer)
+;; Here is the chanage to (or and removal of the redundancy for optional
+;; (defun twofer (&optional name)
+;;   (format nil "One for ~a, one for me." (or name "you")))
+;; Here is just using the format function. There are lots of ~ in there
+;;  and I am not certain how to read this. 
+(defun twofer (&optional name)
+  (format nil "One for ~:[you~;~:*~a~], one for me." name))
-- 
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