Question I'm having trouble with: Using LISP, write a recursive function that takes a list and...

Question I'm having trouble with:   Using LISP, write a recursive function that takes a list and returns the number of times the symbol 'a' occurs in it. Note: do not count a's that might occur in a sublist within the list.

Expert Solution

SOURCE CODE:

*Please follow the comments to better understand the code.

**Please look at the Screenshot below and use this code to copy-paste.

***The code in the below screenshot is neatly indented for better understanding.

; Take a helper function that calculates the count of a .
; starting with count 0

(defun count_a (l)
(labels ((helper (x ans_count)
(if (equalp 'a (car x)) (incf ans_count))
(cond ((null x) ans_count)
(t (helper (cdr x) ans_count)))))
(helper l 0)))

; Test the code here
(write (count_a '(a b (a) c)))

==============================================

SCREENSHOT:

venereology answered 1 month ago

I'm having trouble implementing the merge function on this recursive merge sort. I am not allowed...

I'm having trouble implementing the merge function on this recursive merge sort. I am not allowed to change the parameter list in the functions. This is what I have so far, written in C. So far I've been getting segfaults, and I feel like it's because I'm off by 1, somewhere... void merge_the_array(int *list, int l1, int h1, int l2, int h2){ // create a temp array for l1-h1 int arr_a[(h1-l1)+1]; // create a temp array for l2-h2, adding 1...

Write a LISP function COUNTX which takes an atom and a list and returns the number...

Write a LISP function COUNTX which takes an atom and a list and returns the number of top-level occurrences of the atom in the list. For example: (COUNTX ‘A ‘(A (A B) B A B A (B A)) Returns the value 3, the other two A’s are not at the top level

Write a LISP function POWER that takes a list containing exactly two numeric atoms and computes...

Write a LISP function POWER that takes a list containing exactly two numeric atoms and computes the first atom raised to the power of the second atom. For example: (POWER ‘(2 4) Returns the value 16

Python Question Using lists, write the function non_unique(list) that takes a list list as argument. It...

Python Question Using lists, write the function non_unique(list) that takes a list list as argument. It returns a list which duplicated elements remains and each duplicated element is followed by a number which shows how many times it appears. All elements in return list should be in the same order as their appearance in the original list. For example, given the input [‘a’, ‘b’, ‘c’, ‘a’, ‘b’, ‘d’, ‘a’,‘e’], the function would return [‘a’, 3, ‘b’, 2]. Another example, ['abc',...

I'm having trouble with these few questions out of a long list of journal entries that...

I'm having trouble with these few questions out of a long list of journal entries that I have to record for a project. If you could please state the journal entries for these and why that would be very helpful. Thank you! May 2 – Sold merchandise on credit to Yellow Rock Company, Invoice No. 9501, for $4,500 (cost is $2,000). I get the first part of the journal entry but don't know how to record the cost. May 3...

I'm having trouble creating a histogram using openCV (color segmentation)

Having some trouble with this python question. An answer would be greatly appreciated! #Write a function...

Having some trouble with this python question. An answer would be greatly appreciated! #Write a function called are_anagrams. The function should #have two parameters, a pair of strings. The function should #return True if the strings are anagrams of one another, #False if they are not. # #Two strings are considered anagrams if they have only the #same letters, as well as the same count of each letter. For #this problem, you should ignore spaces and capitalization. # #So, for...

CODE USING LISP... No other language please trim-to (symbol list) Write a function named trim-to that...

CODE USING LISP... No other language please trim-to (symbol list) Write a function named trim-to that takes a symbol and list as parameters. Return a new list starting from the first occurrence of the input symbol in the input list. If there is no occurrence of the symbol, return nil. For example: (trim-to ‘c ‘(a b c d e)) This should return the following list: ‘(c d e) ackermann (number number) Write a function named ackermann that takes two integers....

Write a recursive function, max_in_list(my_list), which takes an non-empty list, my_list, of integers as a parameter....

Write a recursive function, max_in_list(my_list), which takes an non-empty list, my_list, of integers as a parameter. This function calculates and returns the largest value in the list. The base case will probably deal with the scenario where the list has just one value. The recursive case will probably call the function recursively using the original list, but with one item removed. Note: This function has to be recursive; you are not allowed to use loops to solve this problem! Test...

Write LISP functions GEFILTER and LFILTER. GEFILTER takes a numeric atom and a list of numbers...

Write LISP functions GEFILTER and LFILTER. GEFILTER takes a numeric atom and a list of numbers and returns a list consisting all numbers in the list which are greater than or equal to the given number. LFILTER takes a numeric atom and a list of numbers and returns a list consisting of all numbers in the list less than the given number. For example: (GEFILTER 4 ‘(3 5 8 2 4 1 9)) Returns the list (5 8 4 9)...

Question