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| author | Loic GUEGAN <loic.guegan@yahoo.fr> | 2019-01-31 15:31:37 +0100 |
|---|---|---|
| committer | Loic GUEGAN <loic.guegan@yahoo.fr> | 2019-01-31 15:31:37 +0100 |
| commit | d0f6e2ff9cdf4c35e99b54fa765aca7f46ed6a24 (patch) | |
| tree | 7e48a591715e18f3a74324030cb3963c4421cc49 /src/union-find/quick-find.lisp | |
| parent | 0038d9bd0318c1025b8edd005f3aaa609a308a57 (diff) | |
Clean project
Diffstat (limited to 'src/union-find/quick-find.lisp')
| -rw-r--r-- | src/union-find/quick-find.lisp | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/src/union-find/quick-find.lisp b/src/union-find/quick-find.lisp new file mode 100644 index 0000000..edaa7f0 --- /dev/null +++ b/src/union-find/quick-find.lisp @@ -0,0 +1,37 @@ +;;;; Quick Find Algorithm +;;;; This algorithm solve dynamic connectivity +;;;; problem by providing a way to find if there +;;;; is a path between two nodes in a dynamic graph + + +;;; Base functions + +(defun create-network (n) + "Build a quick-find network using a dynamic vector" + (let ((nodes (make-array n :fill-pointer 0))) + (dotimes (id n) + (vector-push id nodes)) + nodes)) + +;; Link two nodes in the network +(defun union_ (network n1 n2) + "Link two nodes in the quick-find network. union_ represent the union operation of the Quick Find Algorithm" + (let ((v-n1 (elt network n1)) + (v-n2 (elt network n2)) + (new-network (copy-seq network))) + (dotimes (n (length new-network)) + (if (= (elt new-network n) v-n2) (setf (elt new-network n) v-n1))) + new-network)) + +;;; Macro definitions + +(defmacro connected (network n1 n2) + " Return t if there is a path between n1 and n2, nil otherwise. connected represent the find operation of the Quick Find Algorithm" + `(= (elt ,network ,n1) (elt ,network ,n2))) + +(defmacro nunion_ (network n1 n2) + "A destructive version of union_" + `(setq ,network (union_ ,network ,n1 ,n2))) + + + |
