EBK BUILDING JAVA PROGRAMS
4th Edition
ISBN: 9780134323718
Author: Stepp
Publisher: PEARSON CUSTOM PUB.(CONSIGNMENT)
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Expert Solution & Answer
Chapter 12, Problem 20E
Explanation of Solution
Method definition:
//All the sub-lists of the given list of Strings gets printed.
/*elements!= null and elements contains no duplicates are the pre-condition*/
//method definition
public static void subsets(List<String> elements)
{
//define the list
List<String> chosen = new ArrayList<String>();
//call the method explore
explore(elements, chosen);
}
/*Helper recursive function defined to explore all the sub list from the given list of elements, choice is made assuming the given list of string is already chosen*/
//method definition
private static void explore(List<String> elements, List<String> chosen)
{
// base case; nothing left to choose
//validate whether the elements are empty
if (elements.isEmpty())
{
//display the chosen
System.out.println(chosen);
}
else
{
//define the choice that is for first element
String first = elements.remove(0);
// two explorations: one with this first element, one without
//add the first element
chosen.add(first);
//call the explore method
explore(elements, chosen);
//remove the element
chosen.remove(chosen.size() - 1);
//call the method
explore(elements, chosen);
// backtrack! 1st element is put back
elements...
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Write a recursive function that finds the minimum value in an ArrayList.
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import java.util.*;
public class RecursiveMin{public static void main(String[] args){Scanner input = new Scanner(System.in);ArrayList<Integer> numbers = new ArrayList<Integer>();while (true){System.out.println("Please enter numbers. Enter -1 to quit: ");int number = input.nextInt();if (number == -1){break;}else {numbers.add(number);}}
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Write a method subsets that uses recursive backtracking to find every possible sub-list of a given list. A sub-list of a list L contains 0 or more of L's elements. Your method should accept a List of strings as its parameter and print every sub-list that could be created from elements of that list, one per line. For example, suppose a variable called list stores the following elements:
[Janet, Robert, Morgan, Char]The call of subsets(list); would produce output such as the following:
[Janet, Robert, Morgan, Char][Janet, Robert, Morgan][Janet, Robert, Char][Janet, Robert][Janet, Morgan, Char][Janet, Morgan][Janet, Char][Janet][Robert, Morgan, Char][Robert, Morgan][Robert, Char][Robert][Morgan, Char][Morgan][Char][][3:07 AM]The order in which you show the sub-lists does not matter, but the order of the elements of each sub-list DOES matter (Note: this requirement is a limitation of Practice-It testing code. The textbook version of the problem would accept an answer with the elements in…
JAVA:
Write a recursive method named threeSum that accepts a list of integers and prints all combinations of three integers in the list that sum to 0. For example, if given the list [-1, 0, 1, 2, -1, -4], print the following lines of output:
[-1, 0, 1] [-1, 2, -1] [0, 1, -1]
You may print the lines of output in any order. The elements in each three-element sublist should appear in the same relative order that they appeared in the original list. Do not print duplicate lists; if the same exact sublist can be made in multiple ways, print it only once. If there are no combinations of three elements that sum to 0, print no output.
The list passed to your method must be back to its original state at the end of the call. Either do not modify it, or if you modify it, fully undo your modifications before the method returns.
Constraints: Do not declare any global variables. You can use any data structures you like, and your code can contain loops, but the overall algorithm must be recursive and…
Chapter 12 Solutions
EBK BUILDING JAVA PROGRAMS
Ch. 12.1 -
What is recursion? How does a recursive method...Ch. 12.1 - Prob. 2SCPCh. 12.1 - Prob. 3SCPCh. 12.1 - Prob. 4SCPCh. 12.1 - Prob. 5SCPCh. 12.1 - Prob. 6SCPCh. 12.1 - Prob. 7SCPCh. 12.2 - Prob. 8SCPCh. 12.2 -
What would be the effect if the code for the...Ch. 12.2 -
What would be the effect if the code for the...
Ch. 12.3 - Prob. 11SCPCh. 12.3 - Prob. 12SCPCh. 12.3 - Prob. 13SCPCh. 12.3 - Prob. 14SCPCh. 12.3 - Prob. 15SCPCh. 12.3 - Prob. 16SCPCh. 12.3 - Prob. 17SCPCh. 12.3 - Prob. 18SCPCh. 12.3 - Prob. 19SCPCh. 12.4 - Prob. 20SCPCh. 12.4 - Prob. 21SCPCh. 12.5 - Why is recursion an effective way to implement a...Ch. 12.5 - Prob. 23SCPCh. 12.5 - Prob. 24SCPCh. 12.5 - Prob. 25SCPCh. 12.5 - Prob. 26SCPCh. 12.5 - Prob. 27SCPCh. 12.5 - Prob. 28SCPCh. 12 - Prob. 1ECh. 12 - Write a method called writeNums that takes an...Ch. 12 - Write a method called writeSequence that accepts...Ch. 12 - Write a recursive method called doubleDigits that...Ch. 12 - Prob. 5ECh. 12 - Prob. 6ECh. 12 - Prob. 7ECh. 12 - Write a recursive method called multiplyEvens that...Ch. 12 - Prob. 9ECh. 12 - Prob. 10ECh. 12 - Prob. 11ECh. 12 - Write a recursive method called isReverse that...Ch. 12 - Prob. 13ECh. 12 - Prob. 14ECh. 12 - Prob. 15ECh. 12 - Prob. 16ECh. 12 - Prob. 17ECh. 12 - Prob. 18ECh. 12 - Prob. 19ECh. 12 - Prob. 20ECh. 12 - Prob. 21ECh. 12 - Prob. 22E
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