Chapter 13, Problem 4PP

Program Plan Intro

Permutation of word

Program plan:

Filename: “PermutationIterator.java”

This program file is used to define a class “PermutationIterator”. In the code,

• Import the required packages.
• Define a class “PermutationIterator”.
  • Define the class members.
  • Define the constructor “PermutationIterator()”.
    • Initialize the class members.
  • Define a method “nextPermutation()”.
    • If the length of the word is equal to 0.
      • Increment “current” by 1.
      • Return an empty string.
        • Declare a variable “c” and assign the character of “word” at “current” position.
        • Call the method “nextPermutation()” and assign the value to “nextpermut”.
        • If the condition “!tailIterator.hasMorePermutations()” is true,
        • • Increment the current by 1.
          • If the “current” is greater than or equal to length of the “word”,
            • Set the value of “tailIterator” as “null”.
          • Else
            • If the “current+1” is greater than or equal to the length of the “word”,
              • Get substring of “word” to “tail”.
                • If the “current+1” is less than the length of the “word”,
                  • Get the substring of “word” to “tail”.
                • Create “tailIterator” as an object of “PermutationIterator”.
        • Return the value of sum of character “c” and string “nextPermut”.
  • Define a method “hasMorePermutations()”.
    • Return the value.

Filename: “PermutationIterator.java”

This program file is used to define a class “PermutationIteratorDemo”. In the code,

• Import the required packages.
• Define a class “PermutationIteratorDemo”.
  • Define the “main” method.
    • Define the object “iter” of “PermutationIterator”.
    • Call the method “nextPermutation()” using “iter” and return the value.
    • Print the expected value.
    • Call the method “nextPermutation()” using “iter” and return the value.
    • Print the expected value.
    • Call the method “nextPermutation()” using “iter” and return the value.
    • Print the expected value.
    • Call the method “nextPermutation()” using “iter” and return the value.
    • Print the expected value.
    • Call the method “nextPermutation()” using “iter” and return the value.
    • Print the expected value.
    • Call the method “nextPermutation()” using “iter” and return the value.
    • Print the expected value.
    • Call the method “nextPermutation()” using “iter” and return the value.
    • Print the expected value.