Ask Question, Ask an Expert


Ask Computer Engineering Expert


You will prepare a C++ program to find the intersection and/or union of two doubly linked lists using recursion. You are not allowed to use the STL Library.

A set is a collection of distinct entities regarded as a unit, being either individually specified or (more usually) satisfying specified conditions. In set theory the union of two sets A and B, is the is the set of all distinct elements in A and B. The intersection of two sets A and B is the set that contains all elements of A that also belong to B (or equivalently, all elements of B that also belong to A), but no other elements. In mathematics, the notion of bag (or multiset) is a generalization of the notion of set in which members are allowed to appear more than once. For this homework we will work with bags.


The input is one script file, in the same format as the script file from Homework 1, and two or more data files containing words. The script file will ask you to read 2 or more files into doubly linked lists and operate on them. Two new operations will be introduced:

union(L1, L2, L3)

will find the union of sets L1 and L2 and store the result in L3.

intersection(L1, L2, L3)

will find the intersection of sets L1 and L2 and store the result in L3.

These new operations will require the modification of the script parser provided by the TA’s. A new version of the parser is posted.

We will define a word as a sequence of characters. These characters can be any of the 95 printable characters, except the space, which will be used as a separator. Words will be up to 30 characters long and will be separated, as mentioned before, by spaces and carriage returns (’\n’). We will not test you with longer words, and we will not use any non-printable characters other than the carriage return and the EOF character.

Notice that words can be capitalized. This should not interfere with your results: a capitalized word is the same as a non-capitalized word for the purposes of this homework. Uppercase letters can be anywhere in the word, for ex.: ”Hungry”, ”hungry” and ”hUngry” should be counted as the same word. By default all uppercase letters should be changed to lowercase. Words will be separated by one or more spaces and one or more carriage returns. For this homework we will not use other separators. The input files will contain no punctuation.Another important detail is that input files might be empty, since the empty set(∅) is a valid in set theory. You can use the properties of the empty set:

A ∪ ∅ = A
A ∩ ∅ = ∅

to produce your results.

In order to simplify the problem, the formatting of the original files will be discarded. All uppercase characters must be changed to lower case. When creating the doubly linked lists in memory you should create them in alphabetical order. You should also keep track of how many times each word appears in the input file. Typically this can be done adding a new field to your node, but you are free to devise your own method.

Program and output specification:

The main program should be called ”recursion”.


recursion script=input.script

Note that the file name will not necessarily be the same every time, so your program will have to take that into account. You can use the Command Line Parser that is provided in the TA’s homepage. When asked to output a doubly linked list to a file you must prepare one word per line followed by a space and the number of occurrences of the word. Please note this change from the previous homework. If the number of occurrences is 0 you must not output the word. Similarly, if the linked list is empty, the file created will be empty. When calculating the intersection of two linked lists you must only keep one copy of each word in the output list.



alpha beta gamma delta Alpha

cat dog bird


alpha 2
beta 1
bird 1
cat 1
delta 1
dog 1
gamma 1

gamma 1
dog 2
delta 1
cat 1
bird 1
beta 1
alpha 3


dog 1
alpha 1


• Your program must be able to create and handle multiple doubly linked lists. (Hint: Think about creating a linked list of linked lists or an array of linked lists)

• When writing to a file you will be asked to prepare either in alphabetical order or in reverse alphabetical order. Since your linked lists will be created in order, this will involve writing starting from the head or from the tail. You don’t need to use recursion to print your files.

• When performing the union and intersection of the linked lists you must use only recursion. Iterators and loops are not allowed. This will be strictly enforced.

• You are allowed to use loops and iterators when reading and writing from a file, in order to recycle the code you used in the previous homework set. However you must create a recursive search method and a recursive list traversing method.

• You must create a log file that records the length of each linked list after each operation. This log file should also be used to output any warnings and errors you might encounter.

• The program should not halt when encountering errors in the script. It should just send a message to the log file and continue with the next line. The only error that is unrecoverable is a missing script file.

• Do not use the STL library.

• Your program should prepare error messages to the screen. Your program should not crash, halt unexpectedly or produce unhandled exceptions. Consider empty input, zeroes and inconsistent information. Each exception will be -10.

• Test cases. Your program will be tested with 10 test scripts, going from easy to difficult. You can assume 80% of test cases will be clean, valid input files.

Computer Engineering, Engineering

  • Category:- Computer Engineering
  • Reference No.:- M9875

Have any Question? 

Related Questions in Computer Engineering

1 authentication using certi fi cates although considered

1. Authentication using certi fi cates, although considered safe, suffers from weaknesses. Discuss these weaknesses using speci fi c examples. 2. Kerberos and SSL are additional layers to enhance authentication. Detail h ...

Assignment apple versus samsungapple ipads continue to be

Assignment : Apple versus Samsung Apple iPads continue to be successful. The Samsung Galaxy Tab is one (1) of iPad's competitors. Use the Internet and Strayer Library to research the advantages and disadvantages of these ...

Abstract data types adts are very important as they serve

Abstract data types (ADTs) are very important as they serve as programming tools that enable component reuse and encapsulation. This assignment requires students to create, implement and apply ADTs in an application.The ...

Adaptive unsharp masking a powerful method of sharpening

(Adaptive unsharp masking) A powerful method of sharpening images in the presence of low levels of noise (such as film grain noise) is via the following algorithm [15] . The high-pass filter which can be used for unsharp ...

1 write a program that can read an indefinite number of

1. Write a program that can read an indefinite number of lines of VB.NET code and store reserved words in one linked list and identifiers and literals in another linked list. When the program is finished reading input, d ...

1 some of the application programs can use the services of

1. Some of the application programs can use the services of two transport-layer protocols (UDP or TCP). When a packet arrives at the destination, how can the computer find which transport layer is involved? 2. A client r ...

You are to design a visual system for detecting small black

You are to design a visual system for detecting small black objects against a tight background. Assume that the image of one of these objects is a square that is 5 pixels wide. Your system is to be used to create a Boole ...

1 what is a vulnerability scanner how is it used to improve

1. What is a vulnerability scanner? How is it used to improve security? 2. What is the difference between active and passive vulnerability scanners? 3. What kind of data and information can be found using a packet sniffe ...

Course takeaway please respond to the followingfrom the

"Course Takeaway" Please respond to the following: From the lessons and conceptual ideas presented in this course, determine the single most impactful or interesting lesson / concept you have learned. Provide a rationale ...

What is the time complexity as a function of the number n

What is the time complexity, as a function of the number n of vertices and m of edges, of the following network operations if the network in question is stored in adjacency list format? a) Calculating the mean degree. b) ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro

Describe what you learned about the impact of economic

Describe what you learned about the impact of economic, social, and demographic trends affecting the US labor environmen