simultaneous operation and swap

1 files changed, 19 insertions, 0 deletions

diff --git a/tree-recursion.rkt b/tree-recursion.rkt
new file mode 100644
index 0000000..031d40f
--- /dev/null
+++ b/tree-recursion.rkt
@@ -0,0 +1,19 @@
+#lang sicp
+(define (myfun n)
+  (cond ((< n 3) n)
+        (else (+ (myfun (- n 1))
+                 (* 2 (myfun (- n 2)))
+                 (* 3 (myfun (- n 3)))))))
+(myfun 11)
+
+(define (myfun2 n)
+  (define (mf i a b c)
+    (cond ((< n 3) n)
+          ((> i n) a)
+          (else (mf (+ i 1) 
+                    (+ a (* 2 b) (* 3 c))
+                    a
+                    b))))
+  (mf 3 2 1 0))
+
+(myfun 11)