3 Largest Prime Factor

1 files changed, 16 insertions, 0 deletions

diff --git a/0003/main.lisp b/0003/main.lisp
new file mode 100644
index 0000000..b2ba414
--- /dev/null
+++ b/0003/main.lisp
@@ -0,0 +1,16 @@
+(defun my-reduce (x y)
+    (if (= 0 (mod x y))
+	(my-reduce (/ x y) y)
+	x))
+
+(defun max-factor-impl (x cur)
+  (let ((next-x (my-reduce x cur)))
+    (if (= 1 next-x)
+	cur
+	(max-factor-impl next-x (+ 1 cur)))))
+
+(defun max-factor (x)
+  (max-factor-impl x 2))
+
+(format t "~&~S~%" (max-factor 600851475143))
+