summaryrefslogtreecommitdiffstats
path: root/net/ricketyspace
diff options
context:
space:
mode:
authorrsiddharth <s@ricketyspace.net>2017-07-01 23:40:14 +0000
committerrsiddharth <s@ricketyspace.net>2017-07-01 23:40:14 +0000
commitd022481e3c3e9337e22b9d92bf805065bd64d05f (patch)
treefbd6cc44794d5f6f3db823d7076703f569baf4de /net/ricketyspace
parent20de4932b291ebd0a24e6fcf5152f972bd80d4e9 (diff)
(net ricketyspace sicp one twentytwo): Add three-primes-gt.
* net/ricketyspace/sicp/one/twentytwo.scm (three-primes-gt) (three-primes-gt-iter): New functions.
Diffstat (limited to 'net/ricketyspace')
-rw-r--r--net/ricketyspace/sicp/one/twentytwo.scm13
1 files changed, 12 insertions, 1 deletions
diff --git a/net/ricketyspace/sicp/one/twentytwo.scm b/net/ricketyspace/sicp/one/twentytwo.scm
index 209afaf..7eab420 100644
--- a/net/ricketyspace/sicp/one/twentytwo.scm
+++ b/net/ricketyspace/sicp/one/twentytwo.scm
@@ -4,8 +4,10 @@
(define-module (net ricketyspace sicp one twentytwo)
#:use-module (net ricketyspace sicp utils)
+ #:use-module (srfi srfi-1)
#:export (timed-prime-test
- search-for-primes))
+ search-for-primes
+ three-primes-gt))
(define (square x)
(expt x 2))
@@ -46,3 +48,12 @@
((odd-and-prime start)
(cons start (search-for-primes (1+ start) end)))
(else (search-for-primes (1+ start) end))))
+
+(define (three-primes-gt n)
+ (three-primes-gt-iter n 10 '()))
+
+(define (three-primes-gt-iter n e l)
+ (cond ((> (length l) 3) (take l 3))
+ (else (three-primes-gt-iter n
+ (+ e 10)
+ (search-for-primes n e)))))