Lisp is a family of programmable programming languages.
5
votes
1answer
125 views
Write a procedure stream-limit that finds
From SICP:
Exercise 3.64. Write a procedure
stream-limit that takes as arguments a
stream and a number (the tolerance).
It should examine the stream until it
finds two successive elements ...
2
votes
1answer
40 views
LISP - Modify string
I have to write a program that changes a string's vowels, consonants and other symbols into C, V respectively 0. I've done this but I wonder if there is a more efficient and elegant way to do it. ...
2
votes
1answer
125 views
Counting Ways to Make Change — Is this good functional/Lisp style?
I have just started learning some Scheme this weekend. I recently solved a problem that goes something like:
Count the number of ways possible to give out a certain amount of change using
1 5 10 25 ...
3
votes
0answers
144 views
Connect Four AI (Minimax) in Clojure
I wrote a Connect Four game inlcuding a AI in Clojure and since I'm rather new to Clojure, some review would be highly appreciated. It can include everything, coding style, simplifications, etc.
But ...
3
votes
0answers
281 views
On Implementing a Lisp
Background:
This began with James Colgan's Lisp-Dojo for Ruby. My implementation can be found here. I then moved on to Write yourself a scheme in 48 hours. This question has to do with one of the ...
2
votes
0answers
116 views
iterative copy-tree in lisp
The common lisp function copy-tree is often implemented in a recursive way,
and thus is prone to stack overflow.
Here is my attempt at writing an iterative version, one-pass, no stack,
no ...
2
votes
0answers
94 views
[SICP ex. 3.22] represent a queue as a procedure with local state
From SICP:
Exercise 3.22. Instead of
representing a queue as a pair of
pointers, we can build a queue as a
procedure with local state. The local
state will consist of pointers to the
...
2
votes
0answers
621 views
Union-set intersection-set for a binary-tree implementation of sets [SICP ex. 2.65]
From SICP:
Exercise 2.65. Use the results of
exercises 2.63 and 2.64 to give (n)
implementations of union-set and
intersection-set for sets implemented
as (balanced) binary trees.41
I ...
1
vote
0answers
60 views
Implementing buffered channels in Guile
I was looking for a way of doing simple message passing in Guile and found some references to the module (ice-9 occam-channel) which is a pretty nifty, but undocumented, module for occam-like ...
1
vote
0answers
128 views
Write a definition of a semaphore in terms of test-and-set! operations
From SICP:
Exercise 3.47. A semaphore (of size
n) is a generalization of a mutex.
Like a mutex, a semaphore supports
acquire and release operations, but it
is more general in that up to n
...
1
vote
0answers
123 views
Write a definition of a semaphore in terms of mutexes
From SICP:
Exercise 3.47. A semaphore (of size
n) is a generalization of a mutex.
Like a mutex, a semaphore supports
acquire and release operations, but it
is more general in that up to n
...
1
vote
0answers
157 views
[SICP ex. 3.17] correctly count the number of pairs in an irregular list structure
From SICP:
For background, here is exercise 3.16:
Exercise 3.16. Ben Bitdiddle decides
to write a procedure to count the
number of pairs in any list structure.
It's easy,'' he reasons.The
...
1
vote
0answers
99 views
[SICP ex. 2.84] coercion of arguments using successive raising
From SICP:
Exercise 2.84. Using the raise
operation of exercise 2.83, modify the
apply-generic procedure so that it
coerces its arguments to have the same
type by the method of successive
...
1
vote
0answers
235 views
(scheme [SICP ex. 2.82] coercion with multiple arguments
From SICP:
Exercise 2.82. Show how to generalize
apply-generic to handle coercion in
the general case of multiple
arguments. One strategy is to attempt
to coerce all the arguments to the
...
1
vote
0answers
213 views
Standard Algebraic Derivative Calculator [SICP ex. 2.58 part b]
I had some difficulty with this problem, so I'm sure there is a better way. Here is the question from SICP:
Exercise 2.58. Suppose we want to
modify the differentiation program so
that it ...
