X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=blobdiff_plain;f=assignment3.mdwn;h=342896c2c429ee51d798d943352d415d682aa7a5;hp=9f64d808f637a1d3c67c1cfa8584e69d0f9e27bf;hb=825c122aac6dd19e421ea72049b608615c00f46a;hpb=71bfc3a4fcf9ae9eddc1854bce2ff6d5f6869644;ds=sidebyside diff --git a/assignment3.mdwn b/assignment3.mdwn index 9f64d808..342896c2 100644 --- a/assignment3.mdwn +++ b/assignment3.mdwn @@ -6,7 +6,8 @@ assignment much faster and more secure. *Writing recursive functions on version 1 style lists* -Recall that version 1 style lists are constructed like this: +Recall that version 1 style lists are constructed like this (see +[[lists and numbers]]):
; booleans @@ -106,14 +107,16 @@ be your base case for your recursive functions that operate on trees. Write a function that sums the number of leaves in a tree. Expected behavior: -let t1 = (make-list 1 nil) -let t2 = (make-list 2 nil) -let t3 = (make-list 3 nil) -let t12 = (make-list t1 (make-list t2 nil)) -let t23 = (make-list t2 (make-list t3 nil)) -let ta = (make-list t1 t23) -let tb = (make-list t12 t3) -let tc = (make-list t1 (make-list t23 nil)) ++ +let t1 = (make-list 1 nil) in +let t2 = (make-list 2 nil) in +let t3 = (make-list 3 nil) in +let t12 = (make-list t1 (make-list t2 nil)) in +let t23 = (make-list t2 (make-list t3 nil)) in +let ta = (make-list t1 t23) in +let tb = (make-list t12 t3) in +let tc = (make-list t1 (make-list t23 nil)) in count-leaves t1 ~~> 1 count-leaves t2 ~~> 2 @@ -123,6 +126,7 @@ count-leaves t23 ~~> 5 count-leaves ta ~~> 6 count-leaves tb ~~> 6 count-leaves tc ~~> 6 +Write a function that counts the number of leaves. @@ -147,3 +151,12 @@ reverse (makeList 1 (makeList 2 (makeList 3 nil))) It may require more resources than my browser is willing to devote to JavaScript.] +; trees +let t1 = (makeList 1 nil) in +let t2 = (makeList 2 nil) in +let t3 = (makeList 3 nil) in +let t12 = (makeList t1 (makeList t2 nil)) in +let t23 = (makeList t2 (makeList t3 nil)) in +let ta = (makeList t1 t23) in +let tb = (makeList t12 t3) in +let tc = (makeList t1 (makeList t23 nil)) in