# HG changeset patch
# User Steve Losh <steve@stevelosh.com>
# Date 1576877039 18000
# Node ID 814719fdaa0d3906ec6b1d9853218f23b6abf7fe
# Parent  ad32169fc54c551478a3e819798c8827bb25f420# Parent  f94bcb40467614422884e1d59d167f24153182ec
Merge.

diff -r f94bcb404676 -r 814719fdaa0d src/problems/dna.lisp
--- a/src/problems/dna.lisp	Fri Mar 01 15:31:38 2019 -0500
+++ b/src/problems/dna.lisp	Fri Dec 20 16:23:59 2019 -0500
@@ -38,4 +38,7 @@
             (gethash #\G results 0)
             (gethash #\T results 0))))
 
-;; (problem-dna "AT")
+
+#; Scratch --------------------------------------------------------------------
+
+(problem-dna "AT")
diff -r f94bcb404676 -r 814719fdaa0d src/problems/rear.lisp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/problems/rear.lisp	Fri Dec 20 16:23:59 2019 -0500
@@ -0,0 +1,66 @@
+(in-package :rosalind)
+
+(defparameter *input-rear* "1 2 3 4 5 6 7 8 9 10
+3 1 5 2 7 4 9 6 10 8
+
+3 10 8 2 5 4 7 1 6 9
+5 2 3 1 7 4 10 8 6 9
+
+8 6 7 9 4 1 3 10 2 5
+8 2 7 6 9 1 5 3 10 4
+
+3 9 10 4 1 8 6 7 5 2
+2 9 8 5 1 7 3 4 6 10
+
+1 2 3 4 5 6 7 8 9 10
+1 2 3 4 5 6 7 8 9 10")
+
+(defparameter *output-rear* "9 4 5 7 0")
+
+(defun bounds-list (start end &key (min-length 0))
+  "Return a list of all subseq bounds between `start` and `end`."
+  (iterate outer
+    (for s :from start :below end)
+    (iterate (for e :from (+ s min-length) :to end)
+      (in outer (collect (cons s e))))))
+
+(defun nreverse-vector (vector &key start end)
+  (iterate (for i :from start)
+           (for j :downfrom (1- end))
+           (repeat (floor (- end start) 2))
+           (rotatef (aref vector i)
+                    (aref vector j)))
+  vector)
+
+(defun reverse-vector (vector &key start end)
+  (nreverse-vector (copy-seq vector) :start start :end end))
+
+(defun reversals (vector &key start end)
+  (iterate (for (s . e) :in (bounds-list start end :min-length 2))
+           (collect (reverse-vector vector :start s :end e))))
+
+(defun reversals-required (from to)
+  (iterate
+    (with remaining = (make-queue)) ; queue of (score . state)
+    (initially (enqueue (cons 0 from) remaining))
+    (for (n . v) = (dequeue remaining))
+    (for start = (mismatch v to))
+    (for end = (mismatch v to :from-end t))
+    (when (null start)
+      (return n))
+    (incf n)
+    (dolist (r (reversals v :start start :end end))
+      (enqueue (cons n r) remaining))))
+
+(define-problem rear (data string)
+    *input-rear*
+    *output-rear*
+  (let ((pairs (-<> data
+                 (str:split (format nil "~2%") <>)
+                 (mapcar (curry #'str:split #\newline) <>)
+                 (mapcar (curry #'mapcar #'read-all-from-string) <>)
+                 (mapcar (curry #'mapcar (rcurry #'coerce 'vector)) <>))))
+    (iterate (for (from to) :in pairs)
+             (collect (time (reversals-required from to))))))
+
+
diff -r f94bcb404676 -r 814719fdaa0d src/problems/subs.lisp
--- a/src/problems/subs.lisp	Fri Mar 01 15:31:38 2019 -0500
+++ b/src/problems/subs.lisp	Fri Dec 20 16:23:59 2019 -0500
@@ -17,6 +17,3 @@
       (collect (1+ pos) :into result)
       (finally (return (str:join " " result))))))
 
-;; (problem-subs)
-;; (solve subs)
-
diff -r f94bcb404676 -r 814719fdaa0d src/problems/tree.lisp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/problems/tree.lisp	Fri Dec 20 16:23:59 2019 -0500
@@ -0,0 +1,49 @@
+(in-package :rosalind)
+
+;; For every edge we add we can link up two previously-unconnected trees.  If we
+;; have N separate trees, we just need N-1 edges to connect them.  So the
+;; problem reduces itself down to just counting the distinct subgraphs of the
+;; given graph.  Some day I really need to add that as a utility function to
+;; cl-digraph.
+
+(defparameter *input-tree*
+  "10
+1 2
+2 8
+4 10
+5 9
+6 10
+7 9")
+
+(defparameter *output-tree*
+  "3")
+
+(defun subgraph-vertices (graph start)
+  (gathering (digraph:map-depth-first #'gather graph start)))
+
+(defun subgraphs (graph)
+  "Return a list of lists of vertices of the distinct subgraphs of `graph`."
+  (let ((graph (digraph:copy-digraph graph)))
+    (iterate
+      (for (values vertex found) = (digraph:arbitrary-vertex graph))
+      (while found)
+      (for subgraph = (subgraph-vertices graph vertex))
+      (collect subgraph)
+      (map nil (curry #'digraph:remove-vertex graph) subgraph))))
+
+(define-problem tree (data stream)
+    *input-tree*
+    *output-tree*
+  (let ((graph (digraph:make-digraph
+                 :initial-vertices (alexandria:iota (read data) :start 1))))
+    (iterate
+      (for line :in-stream data :using #'read-line)
+      (for (a b) = (read-all-from-string line))
+      (digraph:insert-edge graph a b)
+      (digraph:insert-edge graph b a))
+    (1- (length (subgraphs graph)))))
+
+
+#; Scratch --------------------------------------------------------------------
+
+(problem-tree)
diff -r f94bcb404676 -r 814719fdaa0d src/utils.lisp
--- a/src/utils.lisp	Fri Mar 01 15:31:38 2019 -0500
+++ b/src/utils.lisp	Fri Dec 20 16:23:59 2019 -0500
@@ -405,5 +405,7 @@
     (pbcopy (aesthetic-string (funcall problem input)))))
 
 (defmacro solve (name)
+  (assert (symbolp name) ()
+    "Usage: (solve foo)~%foo should not be quoted.")
   `(solve% ',(symb 'problem- name)))