Chapter 9, Problem 10PE

Word Index

Write a program that reads the contents of a text file. The program should create a dictionary in which the key-value pairs are described as follows:

▪ Key. The keys are the individual words found in the file.

▪ Values. Each value is a list that contains the line numbers in the file where the word (the key) is found.

For example, suppose the word “robot” is found in lines 7, 18, 94, and 138. The dictionary would contain an element in which the key was the string “robot", and the value was a list containing the numbers 7, 18, 94, and 138.

Once the dictionary is built, the program should create another text file, known as a word index, listing the contents of the dictionary. The word index file should contain an alphabetical listing of the words that are stored as keys in the dictionary, along with the line numbers where the words appear in the original file. Figure 9-1 shows an example of an original text file (Kennedy.txt) and its index file (index.txt).

Figure 9-1 Example of original file and index file