Recursive breadth first tree traversal

Posted by dugogota on Stack Overflow See other posts from Stack Overflow or by dugogota
Published on 2010-05-03T03:08:08Z Indexed on 2010/05/03 3:18 UTC
Read the original article Hit count: 394

Filed under:

Scheme

|

plt-scheme

|

pltscheme

|

drscheme

I'm pulling my hair out trying to figure out how to implement breadth first tree traversal in scheme. I've done it in Java and C++. If I had code, I'd post it but I'm not sure how exactly to begin.

Given the tree definition below, how to implement breadth first search using recursion?

(define tree1 '( A ( B (C () ()) (D () ()) ) (E (F () ()) (G () ())) ))

Any help, any, is greatly appreciated.

© Stack Overflow or respective owner

Related posts about Scheme

About "If.." in Scheme (plt-scheme)

as seen on Stack Overflow - Search for 'Stack Overflow'
I had a pretty simple requirement in my Scheme program to execute more than one statement, in the true condition of a 'if'. . So I write my code, something like this: (if (= 1 1) ((expression1) (expression2)) ; these 2 expressions are to be executed when the condition is true (expression3)… >>> More
Detecting EOF in a Binary File using Scheme

as seen on Stack Overflow - Search for 'Stack Overflow'
(define (read-all-input) (local ((define line (bytes->list (read-bytes 4)))) (if (eof-object? line) empty (cons line (read-all-input))))) (void (read-all-input)) The above code fails because bytes-list expects an argument of type byte string, but is given # >>> More
Scheme: Detecting duplicate elements in a list

as seen on Stack Overflow - Search for 'Stack Overflow'
Does R6RS or Chez Scheme v7.9.4 have a library function to check if a list contains duplicate elements? Alternatively, do either have any built in functionality for sets (which dis-allow duplicate elements)? So far, I've only been able to find an example here. The problem with that is that it doesn't… >>> More
Scheme implementations - what does it mean?

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I'm a beginning student in CS, and my classes are mostly in Java. I'm currently going through "Little Schemer" as a self study, and in the process of finding out how to do that I have found numerous references to "implementations" of Scheme. My question is, what are implementations? Are they… >>> More
Traversing Scheme function as a list

as seen on Stack Overflow - Search for 'Stack Overflow'
Isn't it possible to treat functions in Scheme as any other list? Basically, what I want do to is something like this: (define (foo) "hello") (cdr foo) ; or similar, should return the list ((foo) "hello") I've found a similar discussion about this, and I feel a bit disappointed if this is not… >>> More

Related posts about plt-scheme

PLT Scheme Extracting field ids from structures

as seen on Stack Overflow - Search for 'Stack Overflow'
I want to see if I can map PLT Scheme structure fields to columns in a DB. I've figured out how to extract accessor functions from structures in PLT scheme using the fourth return value of: (struct-type-info) However the returned procedure indexes into the struct using an integer. Is there… >>> More
PLT Scheme Memory

as seen on Stack Overflow - Search for 'Stack Overflow'
So I need some help with implementing a Make-memory program using Scheme. I need two messages 'write and 'read. So it would be like (mymem 'write 34 -116) and (mymem 'read 99) right? and (define mymem (make-memory 100)).....How would I implement this in scheme? using an Alist???I need some help coding… >>> More
PLT Scheme URL dispatch

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm trying to hook up URL dispatch with PLT Scheme. I've taken a look at the tutorial and the server documentation. I can figure out how to route requests to the same servlets. Specific example: (define (start request) (blog-dispatch request)) (define-values (blog-dispatch blog-url) (dispatch-rules … >>> More
PLT Scheme sort function

as seen on Stack Overflow - Search for 'Stack Overflow'
PLT Scheme guide says that it's implemented sort function is able to sort a list according to an extarcted value using a lambda function. link text The guide provides an unworking code example of this- (sort '(("aardvark") ("dingo") ("cow") ("bear")) #:key car string<?) Which returns… >>> More
plt-scheme : catching mouse click event on canvas

as seen on Stack Overflow - Search for 'Stack Overflow'
I am writing a tic-tac-toe game in plt-scheme as my AI course project. The idea for gui is a grid with 9 boxes, each with a canvas, using panes ... When the user click on a canvas, 'X' or 'O' will be drawn accordingly ... The question is how can I catch mouse click event on canvas? I found out I… >>> More