Introduction to Java Programming and Data Structures, Comprehensive Version (11th Edition)
11th Edition
ISBN: 9780134670942
Author: Y. Daniel Liang
Publisher: PEARSON
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Chapter 18, Problem 18.11PE
Program Plan Intro
Sum the digits in an integer using recursion
- Import required packages.
- Declare the main class named “Main”.
- Give the main method “public static void main ()”.
- Create an object “sc” for the scanner class.
- Get a number and store it in a variable “num”.
- Print the sum of the digits by calling the function “sumDigits ()”.
- Give function definition for the static method “sumDigits ()”.
- Declare a variable “sum” and assign 0 to it.
- Check if the value of “n” is not equal to 0.
- Call the function “sumDigits ()” recursively to calculate the sum of digits.
- Return the variable “sum”.
- Give the main method “public static void main ()”.
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Chapter 18 Solutions
Introduction to Java Programming and Data Structures, Comprehensive Version (11th Edition)
Ch. 18.2 - What is a recursive method? What is an infinite...Ch. 18.2 - Prob. 18.2.2CPCh. 18.2 - Show the output of the following programs and...Ch. 18.2 - Prob. 18.2.4CPCh. 18.2 - Prob. 18.2.5CPCh. 18.2 - Write a recursive mathematical definition for...Ch. 18.3 - Prob. 18.3.1CPCh. 18.3 - What is wrong in the following methods?Ch. 18.3 - Prob. 18.3.3CPCh. 18.4 - Describe the characteristics of recursive methods.
Ch. 18.4 - Prob. 18.4.2CPCh. 18.4 - Prob. 18.4.3CPCh. 18.5 - Prob. 18.5.1CPCh. 18.5 - Prob. 18.5.2CPCh. 18.5 - What is a recursive helper method?Ch. 18.6 - Prob. 18.6.1CPCh. 18.6 - How does the program get all files and directories...Ch. 18.6 - How many times will the getSize method be invoked...Ch. 18.6 - Will the program work if the directory is empty...Ch. 18.6 - Will the program work if line 20 is replaced by...Ch. 18.6 - Will the program work if lines 20 and 21 are...Ch. 18.7 - Prob. 18.7.1CPCh. 18.8 - Prob. 18.8.1CPCh. 18.8 - Prob. 18.8.2CPCh. 18.8 - How many times is the displayTriangles method...Ch. 18.8 - Prob. 18.8.4CPCh. 18.8 - Prob. 18.8.5CPCh. 18.9 - Which of the following statements are true? a. Any...Ch. 18.9 - Prob. 18.9.2CPCh. 18.10 - Identify tail-recursive methods in this chapter.Ch. 18.10 - Rewrite the fib method in Listing 18.2 using tail...Ch. 18 - Prob. 18.1PECh. 18 - Prob. 18.2PECh. 18 - (Compute greatest common divisor using recursion)...Ch. 18 - (Sum series) Write a recursive method to compute...Ch. 18 - (Sum series) Write a recursive method to compute...Ch. 18 - (Sum series) Write a recursive method to compute...Ch. 18 - (Fibonacci series) Modify Listing 18.2,...Ch. 18 - Prob. 18.8PECh. 18 - (Print the characters in a string reversely) Write...Ch. 18 - (Occurrences of a specified character in a string)...Ch. 18 - Prob. 18.11PECh. 18 - (Print the characters in a string reversely)...Ch. 18 - (Find the largest number in an array) Write a...Ch. 18 - (Find the number of uppercase letters in a string)...Ch. 18 - Prob. 18.15PECh. 18 - (Find the number of uppercase letters in an array)...Ch. 18 - (Occurrences of a specified character in an array)...Ch. 18 - (Tower of Hanoi) Modify Listing 18.8,...Ch. 18 - Prob. 18.19PECh. 18 - (Display circles) Write a Java program that...Ch. 18 - (Decimal to binary) Write a recursive method that...Ch. 18 - (Decimal to hex) Write a recursive method that...Ch. 18 - (Binary to decimal) Write a recursive method that...Ch. 18 - (Hex to decimal) Write a recursive method that...Ch. 18 - Prob. 18.25PECh. 18 - (Create a maze) Write a program that will find a...Ch. 18 - (Koch snowflake fractal) The text presented the...Ch. 18 - (Nonrecursive directory size) Rewrite Listing...Ch. 18 - (Number of files in a directory) Write a program...Ch. 18 - (Game: Knights Tour) The Knights Tour is an...Ch. 18 - (Game: Knights Tour animation) Write a program for...Ch. 18 - (Game: Eight Queens) The Eight Queens problem is...Ch. 18 - Prob. 18.35PECh. 18 - (Sierpinski triangle) Write a program that lets...Ch. 18 - (Hilbert curve) The Hilbert curve, first described...Ch. 18 - (Recursive tree) Write a program to display a...Ch. 18 - Prob. 18.39PE
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