Java: An Introduction to Problem Solving and Programming (8th Edition)
8th Edition
ISBN: 9780134462035
Author: Walter Savitch
Publisher: PEARSON
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Chapter 11, Problem 4P
A common example of a recursive formula is one to compute the sum of the first n integers, 1 + 2 + 3 + … + n. The recursive formula can be expressed as
1 + 2 + 3 + … + n = n + (1 + 2 + 3 + … + (n – 1))
Write a static method that implements this recursive formula to compute the sum of the first n integers. Place the method in a test
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JAVA
Question 2:
For two integers m and n, their GCD (Greatest Common Divisor) can be computed by a recursive method. Write a recursive method gcd(m,n) to find their Greatest Common Divisor.
Method body:
If m is 0, the method returns n. If n is 0, the method returns m. If neither is 0, the method can recursively calculate the Greatest Common Divisor with two smaller parameters: One is n, the second one is m mod n (or m % n). The recursive method cannot have loops.
Note: although there are other approaches to calculate Greatest Common Divisor, please follow the instructions in this question, otherwise you will not get the credit.
main method:
Prompt and read in two numbers to find the greatest common divisor.
Call the gcd method with the two numbers as its argument. Print the result to the monitor.
Example program run:
Enter m:
12
Enter n:
28
GCD(12,28) = 4
And here is what I have so far,
package CSCI1302;import java.util.*;public class RecursionDemo {
public static void…
Write a recursive method called digitCount() that takes two integers, n and m as a parameter and returns the number of digits in n that are equal to m. Assume that n≥0 and 0≤m≤9
Ex: If the input is:
34443215 4
3
import java.util.Scanner;
public class LabProgram { /* TODO: Write recursive digitCount() method here. */ public static void main(String[] args) { Scanner scnr = new Scanner(System.in); int digits; int n= scnr.nextInt(); int m= scnr.nextInt(); digits = digitCount(n, m); System.out.println(digits); }}
Chapter 11 Solutions
Java: An Introduction to Problem Solving and Programming (8th Edition)
Ch. 11.1 - What output will be produced by the following...Ch. 11.1 - What is the output produced by the following code?Ch. 11.1 - Write a recursive definition for the following...Ch. 11.1 - What is the output of the following code? public...Ch. 11.1 - Prob. 5STQCh. 11.1 - Complete the definition of the following method....Ch. 11.2 - Revise the method getCount in Listing 11.5 so that...Ch. 11.2 - Prob. 8STQCh. 11.2 - Prob. 9STQCh. 11.2 - Suppose you want me class ArraySearcher to work...
Ch. 11.2 - What Java statement will sort the following array,...Ch. 11.2 - How would you change the class MergeSort so that...Ch. 11.2 - How would you change the class MergeSort so that...Ch. 11.2 - If a value in an array of base type int occurs...Ch. 11.3 - Convert the following event handler to use the...Ch. 11 - What output will be produced by the following...Ch. 11 - What output will be produced by the following...Ch. 11 - Write a recursive method that will compute the...Ch. 11 - Write a recursive method that will compute the sum...Ch. 11 - Complete a recursive definition of the following...Ch. 11 - Write a recursive method that will compute the sum...Ch. 11 - Write a recursive method that will find and return...Ch. 11 - Prob. 8ECh. 11 - Write a recursive method that will compute...Ch. 11 - Suppose we want to compute the amount of money in...Ch. 11 - Prob. 11ECh. 11 - Write a recursive method that will count the...Ch. 11 - Write a recursive method that will remove all the...Ch. 11 - Write a recursive method that will duplicate each...Ch. 11 - Write a recursive method that will reverse the...Ch. 11 - Write a static recursive method that returns the...Ch. 11 - Write a static recursive method that returns the...Ch. 11 - One of the most common examples of recursion is an...Ch. 11 - A common example of a recursive formula is one to...Ch. 11 - A palindrome is a string that reads the same...Ch. 11 - A geometric progression is defined as the product...Ch. 11 - The Fibonacci sequence occurs frequently in nature...Ch. 11 - Prob. 4PPCh. 11 - Once upon a time in a kingdom far away, the king...Ch. 11 - There are n people in a room, where n is an...Ch. 11 - Prob. 7PPCh. 11 - Prob. 10PPCh. 11 - Prob. 12PP
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