11. deep-reverse Define a function similar to the built-in reverse function, except that it acts recursively, reversing the order the members of any nested sublists. You may not use the built-in reverse function as a helper function. However, you may use your own my-reverse function as a helper function. Input: A single list which may contain an arbitrary number of elements and sublists, each sublists may also contain an arbitrary number of elements and sublists, nested to an any depth. Output: A new list which contains all elements in reverse order, as well as recursively reverse order all members of sublists.

11. deep-reverse Define a function similar to the built-in reverse function, except that it acts recursively, reversing the order the members of any nested sublists. You may not use the built-in reverse function as a helper function. However, you may use your own my-reverse function as a helper function. Input: A single list which may contain an arbitrary number of elements and sublists, each sublists may also contain an arbitrary number of elements and sublists, nested to an any depth. Output: A new list which contains all elements in reverse order, as well as recursively reverse order all members of sublists.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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The mapped list pattern Our second pattern is the mapped list pattern, described in video 4 3 mapped list pattern. Often we need to write a function that takes a list as a parameter and returns a new list in which each item in the original list is "mapped" to a new item in the result list. For example, the following function takes a list of numbers as a parameter and returns a list of all the numbers squared, e.g. squares ( [1, 3, 7]) returns [1, 9, 49]. def squares (nums): "Returns the squares of the given numbers""" result = [] for num in nums: result.append (num * num) return result Although this is just a special case of the accumulator pattern, it is so common that we give it its own name: the mapped list pattern. Consider the following function: def squares(nums): ""Returns the squares of the given numbers""" result = [] for num in nums: result.append (num * num) return result If the main program calls print(squares ( [5, -3, 2, 7]) what is the state table for the function…
Exercise B: "Matrix Addition" For this exercise you will design and implement a function that takes two matrix arguments and computes their sum (if and only if a sum can actually be computed, returning an empty list otherwise). Two matrices can only be added together if they have exactly the same dimensions. If the dimensions are acceptable, then the matrix sum will have the same dimensions as either of the operands, and the value of each element in the matrix sum is itself the sum of the corresponding elements in the operand matrices. And although it does makes sense to test rectangularity before attempting addition, you need not perform this step (since you did it above). In order to complete this task, you will need to: ensure you know how matrix addition can be performed² ● Your submission for this exercise:
Write a function named contains-double in Scheme that takes a list as input and returns true if an item every appears twice in a row. You may assume the list is flat (i.e., no nested lists).
Python data structures: write a function that takes in a list (L) as input, and returns the number of inversions. An inversion in L is a pair of elements x and y such that x appears before y in L, but x > y. Your function must run in -place and implement the best possible algoritm of time complexity. def inversions(L: List) -> int:'''finds and returns number of inversions'''
Add the following functions and write a program to test these functions in the class linkedListType: a. Write the definition of a function that returns the data of the kth element of the linked list. If such element is not exist in the list, exit the program. b. Write the definition of a function that deletes the kth element of the linked list. If such element does not exist in the list, exit the program and display message as output.
Exercise 3 Use the function design recipe to develop a function named unique_list. The function takes a list of strings, which may be empty. The function returns a new list that includes the first occurrence of each value in a list and omits later repeats. The returned list should include the first occurrences of values in a list in their original order. For example, if a list contains the following animals ['cat', 'dog', 'cat', 'bug', 'dog', 'ant', 'dog', 'bug'], the unique_list function returns a unique list: ['cat', 'dog', 'bug', 'ant'].
rite a function numPairs that accepts two arguments, a target number and a list of numbers. The function then returns the count of pairs of numbers from the list that sum to the target number. In the first example the answer is 2 because the pairs (0,3) and (1,2) both sum to 3. The pair can be two of the same number, e.g. (2,2) but only if the two 2’s are separate twos in the list.In the last example below, there are three 2’s, so there are three different pairs (2,2) so there are 5 pairs total that sum to 4. Sample usage: >> numPairs( 3, [0,1,2,3] )2
Write the following function that partitions the list using the first element, called a pivot:def partition(lst): After the partition, the elements in the list are rearranged so that all the elements before the pivot are less than or equal to the pivot and the element after the pivot are greater than the pivot. The function also returns the index where the pivot is located in the new list. For example, suppose the list is [5, 2, 9, 3, 6, 8]. After the partition, the list becomes [3, 2, 5, 9, 6, 8]. Implement the function in a way that takes len(lst) comparisons. Write a test program that prompts the user to enter a list and displays the list after the partition.
Practice recursion on lists Practice multiple base conditions Combine recursion call with and,or not operators Search for an element in a list using recursion Instructions In this lab, we will write a recursive function for searching a list of integers/strings. Write a recursive function to determine if a list contains an element. Name the function recursive_search(aList, value), where aList is a list and value if primitive type is the object we want to search for. Return a boolean, specifically True if and only if value is an element of aList else return False from the function Examples: recursive_search([1,2,3], 2) == True recursive_search([1,2,3], 4) == False recursive_search([ ], 4) == False recursive_search([ [ 1 ], 2 ], 1) == False # -----> (because the list contains [ 1 ] and 2, not 1) Hint: Think about what the base case is? When is it obvious that the element is not in the list? If we are not at the base case, how can you use the information about the first element of the…
Q3 Racket Number Function Suppose that into the Racket evaluator we enter the definition: (define dozen 12) Give the value of the Racket expression: (number? dozen). Note that the value should be consistent with the Racket language. Enter your answer here Save Answer Q4 Racket Empty Lists Give two ways to write a Racket expression of which the value is a one-element list with the empty list as its element. Enter your answer here Save Answer
Write a function set_elements() that assigns 1 to the last and fifth elements of a list parameter. Ex: If the input is: One man's trash is another man's treasure then the output is: ['One', "man's", 'trash', 'is', 1, "man's", 1] ''' Your code goes here ''' vals_to_update = input().split() set_elements(vals_to_update) print(vals_to_update)
Make List Items Uppercase 2 in python Define the function make_uppercase(mylist), which takes a list parameter mylist (a list of strings), mutates the list by uppercasing each string in mylist. The function returns None. For example, if mylist is ['cat', 'Dog', 'frOG'], then the mutated list should be ['CAT', 'DOG', 'FROG']. For example: Test Result mylist = ['cat', 'Dog', 'frOG'] result = make_uppercase(mylist) print(mylist) if result != None: print("Error, return value should be None") ['CAT', 'DOG', 'FROG'] mylist = ['baNanas', 'appLes', 'pEAches', 'PEArs'] result = make_uppercase(mylist) print(mylist) if result != None: print("Error, return value should be None") ['BANANAS', 'APPLES', 'PEACHES', 'PEARS']