Task

Given the following list of words

{ant, bat, cat, cot, cut, dog, dot, hen, pig, rat}

The word “cat” can be transformed to the word “dog” in three steps if you are allowed to change at most one character in every step

Step 1: cat => cot

Step 2: cot => dot

Step 3: dot => dog

Note, there might be other ways to transform cat into dog, but the above solution is the quickest as it takes the fewest number of steps.

Also note that every intermediate word used in the transformation (i.e., cot & dot) should be present in the given list of words. So, a transformation like cat => cot => cog => dog is invalid as cog is not part of the valid list of words.

Finally, it might not be possible always to transform one word to another.

Problem Statement:

Implement a Java program that will print the transformation steps required to convert one word to another word.

Input:

Your program will accept a filename as command line argument. You can assume that the file will be present in the same folder from where your program will be executed. The file will be a text file of the following structure.

Line 1: start_word, end_word

Line 2: Comma separated list of all the valid words

Expected output:

You program should write the answer to the standard input (using System.out.print()) in the following format

start_word, word_1, word_2, word_3,…end_word

If the start_word cannot be transformed to the end_word, then your program should print

Cannot transform start_word to end_word”

In case of any errors are exception scenarios (like file not found, for example), your program should print the text “ERROR:“ followed by some user friendly description of the error / exception. For example

ERROR: File not found

• Understand the algorithm being implied from the task
• Implement quick test to demonstrate
  • understanding of algorithm
  • file processing

    Your program will accept a filename as command line argument

• State improvements to code implementation

• All files to be processed must follow rules mentioned in the Input section
• All words in the list of all valid words are in lowercase
  • Why I have not added any ignore case checks;
  • Also, why I have not transformed these list of words into lowercase

• Use a dependency injection framework for injecting dependencies
• Use a logging library instead of Systmem.out.println

• Java 17+ installed

• Extract word-transformer.zip
• Change directory into word-transfer directory
  • Main class is located in com.sg.WordTransformer

• Run below command

  mvnw.cmd clean compile exec:java -Dexec.arguments="data/filedata.txt"

• Run below command

  ./mvnw clean compile exec:java -Dexec.arguments="data/filedata.txt"

• Successful transformation

• Unsuccessful (with none existent file name passed)

• Unsuccessful (with cannot transform error)