Recursive Function To Test All Combinations?
May 17, 2014I am not sure how to add all the possibilities of elements in an array and find the greatest sum. I want to do this recursively. I don't need any code. How I would do it.
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Fibonacci Number - Recursive Function
Jul 8, 2014I wrote this tail recursive function that mirrors the iterative version, except that the loop in the iterative version is replaced by an if statement here and then a recursive call. Is this truly recursive? I have seen the fibo(n-1) + fibo(n - 2) version, but is this also an acceptable recursive solution? Why is it never solved this way?
public class FiboRecursive {
public static int fibo (int n) {
int sum = 0;
int n1 = 1;
int n2 = 1;
if (n == 1 || n == 2) {
sum = 1;
[Code] ...
Calculating Arithmetic Expression - Recursive Function
Oct 26, 2014I have a given arithmetic expression, which form is (A+B) or (A-B), were A and B are either numbers from 0-9, or another ARITHMETIC Expression.
The first thing that comes to my mind is a recursive function, but how to start...
Test That A Function Has No Any Exceptions
Aug 3, 2014I want to test that a function has no any exceptions.In C++ and Google Test Framework (GTest) it will look like this:
ASSERT_NO_THROW({
actual = divide(a, b);
});
How will it look in Java?
Combinations Of Letters To Form Symbols
Nov 19, 2014My professor is a man who enjoys making his students form large, but often simple symbols with smaller letters. That might not have clarified much, so let me demonstrate:
VVVVVVV
VVVVV
VVV
V
Or...
X X
X X
X
X X
X X
Or lastly...
O
O O
O O
O O
O
My problem is, that I've always been bad at figuring out the logic behind these.
I can kinda' see it (somewhat) in my head though... I'd need a double for-loop which depend on the sizes, one that monitors the spaces and one that monitors the symbols, with some conditionals in there. How to make symbols like this, using letters, in Java.
Generating All Combinations Of Characters Given A Length N
Nov 10, 2014I am trying to iterate through all combinations of characters given a length n with the added notion that all characters are numerical (0-9).e.g I have been given n = 5. The I want to iterate through all combinations starting with "00000" and ending with "99999". My first instinct was to just have a for loop like the following:
for(int i= 0; i<99999; i++){
// extra code here
}
but obviously this does not a account for combinations such as "00010".
Number Combinations - Restrict Outputs To Suits Of 3 Numbers
Jul 29, 2014I want to be able to
(A) Restrict the number of output values per line to 3 numbers,
(B) Remove Duplicate lines, where the same numbers are duplicated just outputted in a different order.
(C) Count the number of outlines
(D) Add a fixed column to the outputs that has an ascending count from 1 upwards
I'm trying to achieve. The code is as follows:
package num.com.t1;
import java.util.*;
import java.util.concurrent.atomic.AtomicInteger;
/**
*
*
*/
public class NumComT1 {
public static void main(String... args) {
[Code] ....
JSF :: Call Function Inside Other Function
Jun 23, 2014I would use the return value of a function how parameter of other function..In java is:
// the call produce "YES"
SecondClassController.funcSecondClass(FirstClassController.funcFirstClass());
In my web page I need to do something like this:
[...]
<h:outputText value="#{secondClassController.funcSecondClass(#{firstClassController.funcFirstClass()})}" />
[...]
obtain:
javax.servlet.ServletException JBWEB006007: Failed to parse the expression
@Named
@SessionScoped
public class FirstClassController implements Serializable{
[...]
[code]....
Non-recursive BST Insertion?
Apr 6, 2014I'm trying to implement a non-recursive version of the insertion method, but I'm having a bit of trouble. From what I can tell, it's only returning the last two node..
public void insert(Key key, Value val) {
root = insert(key, val, root);
} private Node insert(Key key, Value val, Node x) {
if(x == null) {
x = new Node(key, val, 1);
[code].....
Recursive Selection Sort
Oct 21, 2014How would I modify this version of a selection sort into a recursive method?
public static void selectionSortRecursive(Comparable [] list, int n)
{
int min;
Comparable temp;
[code]....
Recursive Method For A Tree
May 9, 2015As one of the methods of my IntTree tree I have to implement a method that multiplies the level number with the sum of the nodes on the current level. So far I have this, and it doesn't work. What I am wondering is am I on the right track at all with the second return statement?
public int depthSum(){
return depthSum(overallRoot);
}
private int depthSum(IntTreeNode root) {
if(root==null)
return 0;
int level = 0;
[code]....
Recursive Implantation For Setting Objects
Apr 8, 2015I have a requirement where I have a class as Page which itself contains ArrayList<Page>.Here ArrayList<Page> is nothing but the pages which are accessible from the base Page.I know the depth level ( reading from file) which means how many level I need to go to identify more pages.BUT the problem is how to set the base Page class. I need to set the base Page class but for that I need the objects for the subsequent pages and hence an iterative type of implementation.
View Replies View RelatedTracing Recursive Method That Calculates GCD
May 3, 2014I have this code and i want to trace it
public static int GCD ( int x , int y ) {
if ( y == 0 )
return x;
else if ( x >= y && y > 0)
return GCD ( y , x % y );
else return GCD ( y , x );
}
(it is a recursive method that calculates the greatest common divisor using Euclidean method )
while x = 32 and y = 46
I want here to understand how the code work ? Precisely , composition and decomposition operations.
Why Recursive Method Continue To Return 0
Nov 13, 2014I was told to write a method that adds up the sequence of the formula (n/2n+1) eg. 1/3 + 2/5 + 3/7 etc. simple enough i suppose. my method is below
public static double Series(int n){
if (n==0)return 0;
else return (n/(n*2+1)) + Series(n - 1);
}
However for some reason or another it returns 0 for any number that is put in. I've written it dozens of different ways with no change and i feel like something fairly obvious is being missed on my part. I am honestly intrigued and interested as to why this is happening. i assume it has something to do with the way i put the actual formula in cause if i put anything else in like simply n the recursion would work as expected.
Recursive Method And Printing Out Stars?
Nov 23, 2014KtMok1t.jpg
Below is what I go so far, but how to do star C and E.
public class PrintTriangle
{
public static void printStars (int star)
{
for (int number = 0; number < star;number ++)
{
System.out.print("*");
[Code] ....
Recursive Program - Choose K Objects Out Of N
Apr 20, 2015I recently wrote a simple recursive program that chooses K objects out of N (I was asked to use the variables N choose the R, however) total objects. Here is the code:
int n = 0;
int r = 0;
//the total number of objects defaults to 0
String nChoice = JOptionPane.showInputDialog(null, "How many objects are there to choose from?");
String rChoice = JOptionPane.showInputDialog(null, "How many object are to be chosen from this group?");
try {
n = Integer.parseInt(nChoice);
[Code] ....
It works fine, however in my class we were given two different formula to implement into our code. I used the one above, obviously. However, the second formula we were given was:
C(n,R) = n!
-------(R!(n-R)!)
I had to get the spacing right.
How do I read this formula? How could it be implemented? What are the benefits (if there are any) from using one method over the other? Which method of calculating N choose K (or, in my case, N choose R) would be more widely accepted?
Recursive Method Called RangeSum
Oct 3, 2014I'm trying to understand the concept behind this recursive method called rangeSum. This method sums a range of array elements with recursion. I tried summing the elements of 2 through 5, and I tried writing down what actually happens when java executes the program, but what I get when I try to figure it out by paper is different from what netbeans gives me. Here is a snapshot of my scratch work as well as my source code. Netbeans gives me "The sum of elements 2 through 5 is 18" when I try running it but it I get 12 when I do the recursion on paper. I know that the source code is correct because it's out of the book but what am I doing wrong when I try figuring it out by hand?
XML Code:
package recursivecall;
import java.util.Scanner;
/**
* Author: <<Conrado Sanchez>> Date: Task:
*/
public class RecursiveCall {
public static void main(String[] args) {
[code]....
Recursive Method To Remove Vowels In A String
Oct 22, 2014Write down a recursive method to remove vowels in string ....
View Replies View RelatedMaking Selection Sort Into A Recursive Method
Oct 21, 2014How would I modify this version of a selection sort into a recursive method?
public static void selectionSortRecursive(Comparable [] list, int n)
{
int min;
Comparable temp;
for(int index =0; index < n-1; index++){
min = index;
[code]....
Recursive Program To Change Two Four Letter Words Into Each Other?
Oct 28, 2014SO for my project, we have to create a program where we input two four letter words, and using a list of words our teacher provided us and only changing one letter at a time, make the words match.For example, you input BALD and CALL and it would output BALD BALL CALLWe have to use recursion to do this, and I'm totally lost as to where to even begin.
View Replies View RelatedRecursive Method Using Technique Calling Tree
May 9, 2014a)Write a method that recursively displays any given character the specified number of times on one line.For example, the call: displayRowOf Characters(,5);
Produce a line: *****Write another method that uses a for-loop to perform the same process.
B is something like this ?
for (i=1; i<=n; i++)
i= '*' * n;
System.out.print(i);
Writing A Recursive Merge Sort Algorithm
Mar 27, 2015I have this assignment to write a Merge Sort algorithm using recursion. To start I have a very tough time picturing what is happening when it comes to recursion, but I do understand how merge sorting works. At the moment I feel as though a very good portion of my code is correct, but I am having trouble with the recursion in the main method [ mergeSort(Queue<T> queue) ].
I have another 4 or so hours to pass in my assignment finished or not, and at this point I can honestly say I have no clue how to make my code work. I tried working through the problem on paper with a simple queue of size 3, but even that is a struggle. On paper my code works perfectly fine, so there is definitely something I am missing.
Below is what I have along with my JUnit test.
Java Code:
private Queue<T> output = new Queue<T>();
private Queue<T> output1 = new Queue<T>();
private Queue<T> output2 = new Queue<T>();
public Queue<T> mergeSort(Queue<T> queue) {
// TODO 1
if(queue.size() <= 1) {
return queue;
[Code] .....
How To Resolve StackOverFlowError When Using Recursive Method Call
Mar 24, 2014I have 3 Xml documents that look like this:
model1:
Java Code: <?xml version="1.0" encoding="UTF-8"?>
<model>
<id>1</id>
<nodes>
<id>2</id>
<stencil>TASK</stencil>
</nodes>
<nodes>
<id>3</id>
<stencil>MODEL</stencil>
[Code] ....
After unmarshalling/marshalling in the main class I have created this 3 methods:
Java Code:
public List<Task> extractTasks(Model model) {
List<Task> tasks = new ArrayList<Task>();
for (ModelNodes modelNodes : model.getNodes()) {
if (modelNodes.getStencil().equals("TASK")) {
tasks.add(new Task(modelNodes.getId()));
[Code] ....
When the recursive call to the extractSubModels method is made, I get a **java.lang.StackOverFlowError** ...
Recursive Backtracking Solution - How To Cache Answers Into Appropriate Array
Jan 23, 2014I can often write a recursive backtracking solution, but don't know how to cache the answers into an appropriate array.
For example:
Java Code:
public static int max(int[] costs, int index, int total, int shares) {
if(index >= costs.length) {
return total;
}
int buy = max(costs, index + 1, total - costs[index], shares + 1); // buy one stock
int sell = max(costs, index + 1, total + shares * costs[index], 0); // sell all stocks
return Math.max(total, Math.max(buy, sell)); // compares between buy, sell, and doing nothing
} mh_sh_highlight_all('java');
This is a dynamic programming exercise, but I have no idea what dimensions the dp array should be (I was thinking maybe dp[index][total][shares], but that seemed like overkill). Is this just because my understanding of recursion isn't solid enough or am I missing something else?
Recursive Method - Calculate Greatest Common Divisor Using Euclidean Method
Apr 29, 2014Consider the following recursive method that calculates the greatest common divisor using Euclidean method.
PHP Code:
public static int GCD ( int x , int y )
{
if ( y == 0 )
return x;
else if ( x >= y && y > 0)
return GCD ( y , x % y );
else return GCD ( y , x );
}
Trace the above method for x=32 and y=46
Running A Test With A File?
Jun 11, 2014I just wrote a java program with eclipse that has to read many-many inputs from the user. I want to test it, but I really don't want to type it everytime again and again...
Can I just write all inputs in a text file and let eclipse read this file so instead of typing it again and again, Eclipse reads every line whenever it waits for a user input?