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How do you make it so that when you enter a number it puts a space between each integer

import java.util.Scanner;
public class Digits {
public static void main(String[] args) {
/*
*
count = 1
temp = n
while (temp > 10)
Increment count.
Divide temp by 10.0.
*/
//Assignment: fix this code to print: 1 2 3 (for 123)
//temp = 3426 -> 3 4 2 6
Scanner input = new Scanner(System.in);
System.out.print("Enter an integer: ");
int count = 1;
int temp = input.nextInt();
while(temp >= 10){
count++;
temp = temp / 10;
System.out.print(temp + " ");
}
}
}
Need help fixing code.
Example: when you type 123 it becomes 1 2 3.

Your code is dividing by ten each time, that could be used to print the value in reverse. To print it forward you need a bit more math involving logarithms. Sometime like,
Scanner input = new Scanner(System.in);
System.out.print("Enter an integer: ");
int temp = input.nextInt();
while (temp > 0) {
int p = (int) (Math.log(temp) / Math.log(10));
int v = (int) (temp / Math.pow(10, p));
System.out.print(v + " ");
temp -= v * Math.pow(10, p);
}
Alternatively, read a line of input. Strip out all non digits and then print every character separated by a space. Like,
String temp = input.nextLine().replaceAll("\\D", "");
System.out.println(temp.replaceAll("(.)", "$1 "));

Most of your code is correct, and what you are trying to do is divide by 10 and then print out the value - this probably should have been a modulus operation % to get the remainder of the operation and print that out - but a nice way of thinking about it.
Nevertheless.
You can just use a string and then split the string on each character
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("Enter an integer: ");
// we know that we are going to get some input - so we will just grab it as a String
// whilst we are expecting an int - we will test this later.
// we are doing this as it makes it easier to split the contents of a string
String temp = input.next();
// is this an int? - we will test this first
try {
// if this parsing fails - then it will throw a java.lang.NumberFormat exception
// see the catch block below
int test = Integer.parseInt(temp);
// at this point it is an int no exception was thrown- so let's go
// through and start printing out each character with a space after it
// the temp(which is a string).toCharArray returns a char[] which we
// can just iterate through and set the variable of each iteration to 'c'
for (char c : temp.toCharArray()) {
// now we are going to print out the character with a space after it
System.out.print(c + " ");
}
} catch (NumberFormatException ex){
// this is not an int as we got a number format exception...
System.out.println("You did not enter an integer. :(");
}
// be nice and close the resource
input.close();
}

Answering solely your question, you can use this one-line code.
int test = 123;
System.out.println(String.join(" ", Integer.toString(test).split("")));
Output is: 1 2 3

I have a problem with splitting up my Java program into separate methods within the same class, could I have some advice on how to go about it?

I was given the task of splitting my program which which allows the user to enter an array of numbers and after an odd number between 1 and 10 to check whether the odd number is a factor of each of the 5 numbers in the array. I keep on trying out different ways but none seem to work. Could someone help me out or send a sample of how I should sort it? This is the program:
import java.util.Scanner;
public class CheckboxExample{
public static void main(String args[]) {
CheckBox c = new CheckBox();
new CheckboxExample(); // links to checkbox class
Scanner s = new Scanner(System.in);
int array[] = new int[10];
System.out.println ("Please enter 10 random numbers"); // prompts the user to enter 10 numbers
int num; // declares variable num
try{
for (int i = 0; i < 10; i++) {
array[i] = s.nextInt(); // array declaration
}
}catch (Exception e){
System.out.println ("You have an error");
}
System.out.println ("Please enter an odd number between 1 and 10");
try{
num = s.nextInt ();
if (num % 2 == 0){
do{
System.out.println ("\nYour number is even, enter an odd one");
num = s.nextInt ();
}while (num % 2 == 0);
}
if (num < 0 | num > 10){
do{
System.out.println ("Your number is outside of the range, try again");
num = s.nextInt ();
}while (num < 0 | num > 10);
}
for (int i = 0; i < 5 ; i++){
if (array[i] % num == 0) {
System.out.println("Your number is a factor of " + array[i] );
}
}
}catch (Exception e){
System.out.println ("error");
}
}
}

A method should ideally be responsible for one task. In your case you should think about the different things your code try to do and organize them in a sense that each of the methods you call does one thing of the list of things you try to do.
As an example: As far as I understand your code does the following things:
Read an array of 10 values
Read an odd number
Verify the number is odd
Verify the number is in range
Calculate if the number is a factor of one of the 10 numbers in the array
Now one possible approach would be to separate your code in 5 methods that do exactly these things.
At first you call the method that reads the 10 numbers.
Then you call the method to read the odd number.
3. and 4. are actually part of reading the number, since you need to retry on an invalid input, so you could write your method for inputting the odd number in a way that it uses the methods for verifying the input.
Finally when you have all the valid input, you call the method which produces your result (ie. if the number is a factor of the numbers in the list).
A general outlier for your code could look like:
public class CheckboxExample {
public static void main(String args[]) {
CheckBox c = new CheckBox();
new CheckboxExample(); // links to checkbox class
Scanner s = new Scanner(System.in);
int array[] = readInputArray();
int number = readOddValue();
calculateFactors(array, number);
}
private int[] readInputArray() {...}
private int readOddValue() {...}
private void calculateFactors(int[] array, int number) {...}
//additional methods used by readOddValue which verify if the value is actually odd
}
Please note that this is just one way to split your code into methods and there are several ways to design and implement each of these methods.

Java Sum of numbers until string is entered

i've just started java programming and was wondering on how to approach or solve this problem i'm faced with.
I have to write a program that asks a user for a number and continually sums the numbers inputted and print the result.
This program stops when the user enters "END"
I just can't seem to think of a solution to this problem, any help or guidance throughout this problem would be much appreciated and would really help me understand problems like this. This is the best i could do
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
while (true) {
System.out.print("Enter a number: ");
int x = scan.nextInt();
System.out.print("Enter a number: ");
int y = scan.nextInt();
int sum = x + y;
System.out.println("Sum is now: " + sum);
}
}
}
The output is supposed to look like this:
Enter a number: 5
Sum is now: 5
Enter a number: 10
Sum is now: 15
Enter a number: END

One solution would be to not use the Scanner#nextInt() method at all but instead utilize the Scanner#nextLine() method and confirm the entry of the numerical entry with the String#matches() method along with a small Regular Expression (RegEx) of "\d+". This expression checks to see if the entire string contains nothing but numerical digits. If it does then the matches() method returns true otherwise it returns false.
Scanner scan = new Scanner(System.in);
int sum = 0;
String val = "";
while (val.equals("")) {
System.out.print("Enter a number (END to quit): ");
val = scan.nextLine();
// Was the word 'end' in any letter case supplied?
if (val.equalsIgnoreCase("end")) {
// Yes, so break out of loop.
break;
}
// Was a string representation of a
// integer numerical value supplied?
else if (val.matches("\\-?\\+?\\d+")) {
// Yes, convert the string to integer and sum it.
sum += Integer.parseInt(val);
System.out.println("Sum is now: " + sum); // Display Sum
}
// No, inform User of Invalid entry
else {
System.err.println("Invalid number supplied! Try again...");
}
val = ""; // Clear val to continue looping
}
// Broken out of loop with the entry of 'End"
System.out.println("Application ENDED");
EDIT: Based on Comment:
Since since an integer can be signed (ie: -20) or unsigned (ie: 20) and the fact that an Integer can be prefixed with a + (ie: +20) which is the same as unsigned 20, the code snippet above takes this into consideration.

Do it like this:
public static void main(String[] args) throws Exception {
int sum = 0;
Scanner scan = new Scanner(System.in);
while (scan.hasNext()) {
System.out.print("Enter a number: ");
if (scan.hasNextInt())
sum += scan.nextInt();
else
break;
System.out.println("Sum is now: " + sum);
}
System.out.print("END");
}
This will end if the input is not a number (int).
As pointed out in the comments, if you want the program to stop when the user specifically enters "END", change the else-statement to:
else if (scanner.next().equals("END"))
break;

Prompt user to enter values until the same value is entered thrice in a row

I have a question regarding loops. Basically the program rotates around prompting user to enter integers until three integers have been entered which are the same ones but the issue is if i enter a different integer at the beginning and then enter three same integer i am not able to make my program accept it as three similar integer in the row..
This is the actual question: Write a Java program that prompts the user to enter integers from the keyboard one at a time. The program stops reading integers once the user enters the same value three times consecutively (meaning three times in a row, one after the other). Once input is completed the program is to display the message “Same entered 3 in a row
output:
Enter an integer: 77
Enter an integer: 56
Enter an integer: 56
Enter an integer: 78
Enter an integer: 56
Enter an integer: 22
Enter an integer: 22
Enter an integer: 22
Same integer value entered thrice
I am not able to get the above output correctly. Can anyone please help me in this..
Here is the same program which i tried:
import java.util.Scanner;
public class Naim5c
{
public static void main(String args[])
{
Scanner input = new Scanner(System.in);
int count = 0;
int a,b,c;
do{
System.out.println("enter an integer");
a = input.nextInt();
System.out.println("enter an integer");
b = input.nextInt();
System.out.println("enter an integer");
c = input.nextInt();
if(a==b)
{
if(b==c)
{
System.out.println("Same integer entered thrice");
}
}
else if (b==c)
{
System.out.println("enter an integer");
a = input.nextInt();
if(c==a)
{
System.out.println("Same integer entered thrice");
}
}
//System.out.println("enter an integer");
//a = input.nextInt();
else if (c==a)
{
System.out.println("enter an integer");
b = input.nextInt();
if( a==b )
{
System.out.println("Same integer entered thrice");
}
}
}while(a!=b && b!=c);
}
}

By the look of it (at least according to you) you require the need to detect when a User enters three integer numbers of the same value three times in a row rather than throughout the entire entry cycle. All you really need is a counter variable and another integer variable to hold the previously entered value. Something like this:
Scanner input = new Scanner(System.in);
int a; // To hold User's current entry value.
int count = 0; // To hold the number of times the same value was entered.
int prevInt = 0; // To hold the value previously entered.
do{
// Since we're in a loop we only need to have
// a single prompt.
System.out.print("Enter an integer: --> ");
a = input.nextInt(); // Get User Input
// Is User entry equal to what what entered
// previously?
if (a == prevInt) {
// Yes it is...
count++; // Increment our counter
// if our counter reaches 3 then let's
// break out of our do/loop.
if (count == 3) { break; }
// Otherwise let's continue the loop from
// the start.
continue;
}
// Nope, not equal to the User's last entry so
// let's make prevInt hold the Users new entry.
prevInt = a;
// Let's reset our counter to 1. We need to set
// to 1 because the last User's input which is
// now held in prevInt is the actual first entry
// for the new integer value.
count = 1;
} while(count < 3); // Keep looping if our counter is less than 3
// Display that a triple entry was made.
System.out.println("Same integer (" + a + ") entered thrice");

You don't need three variables. Just one variable for remembering the last int and a counter variable for recording how many times you've seen the last integer.
int count = 0;
Integer prevInt = null;
do {
System.out.println("enter an integer");
int i = input.nextInt();
if (prevInt == null || i != prevInt) {
count = 1;
} else {
count++;
}
prevInt = i;
} while (count != 3);
System.out.println("Same integer value entered thrice");

You can try this.
Scanner input = new Scanner(System.in);
int num = 0; //holds the current input
boolean check = false; // checking for the input
ArrayList<Integer> number = new ArrayList<Integer>();
do {
System.out.println("Enter an integer");
num = input.nextInt();
number.add(num); // add the current input to the array list
if (number.size() >= 3) { // check if there's 3 or more values in the array
if (number.get(number.size() - 1) == number.get(number.size() - 2) && number.get(number.size() - 2) == number.get(number.size() - 3))
{ // check for input if the same
check = true;
System.out.println("\nSame integer value entered thrice");
}
}
} while(check == false);
// checking for loop to continue of no 3 consecutive input of number is the same

Hello if you want to make a loop you need the for command. And loops uses arrays
int[] I = new int[3]
for(j=0;j<3;j++)
{
System.out.println("enter an integer");
I[j] =input.nextInt();
}
if(I[0]==I[1] || I[1]==I[2]){
System.out.println("Same integer entered thrice");
continue;
}
Assume that code is inside your do while code. Feel free to reply if you have questions
You should simply loop everything back to inputing using "continue".

How to input a lot of data until you type in an invalid number in java

User inputs numbers one by one and then once they type in an invalid number (has to be from 1-200) the program calculates the average of the numbers that were inputted.
I'm just wondering what would the code be for this. I know the one for inputting one piece of data. Example would be:
`Scanner in = new Scanner(System.in);
String numberOfShoes = "";
System.out.println("Enter the number of shoes you want: (0-200) ");
numberOfShoes = in.nextLine();`
this is just an example, but this time I want the user to input a lot of numbers. I know I'm going to include a loop somewhere in this and I have to stop it once it contains an invalid number (using a try catch block).
* I would also like to add that once the user inputs another number it always goes to the next line.

Just use a while loop to continue taking input until a condition is met. Also keep variables to track the sum, and the total number of inputs.
I would also suggest having numberOfShoes be an int and use the nextInt() method on your Scanner (so you don't have to convert from String to int).
System.out.println("Enter your number of shoes: ");
Scanner in = new Scanner(System.in);
int numberOfShoes = 0;
int sum = 0;
int numberOfInputs = 0;
do {
numberOfShoes = in.nextInt();
if (numberOfShoes >= 1 && numberOfShoes <= 200) { // if valid input
sum += numberOfShoes;
numberOfInputs++;
}
} while (numberOfShoes >= 1 && numberOfShoes <= 200); // continue while valid
double average = (double)sum / numberOfInputs;
System.out.println("Average: " + average);
Sample:
Enter your number of shoes:
5
3
7
2
0
Average: 4.25
It added 5 + 3 + 7 + 2 to get the sum of 17. Then it divided 17 by the numberOfInputs, which is 4 to get 4.25

you are almost there.
Logic is like this,
Define array
Begin Loop
Accept the number
check if its invalid number [it is how u define a invalid number]
if invalid, Exit Loop
else put it in the array
End Loop
Add all numbers in your array

I think you need to do something like this (which #Takendarkk suggested):
import java.util.Scanner;
public class shoes {
public void main(String[] args){
int input = 0;
do{
Scanner in = new Scanner(System.in);
String numberOfShoes = "";
System.out.println("Enter the number of shoes you want: (0-200) ");
numberOfShoes = in.nextLine();
input = Integer.parseInt(numberOfShoes);
}while((input>=0) && (input<=200));
}
}

you can use for loop like this
for(::)
{
//do your input and processing here
if(terminating condition satisified)
{
break;
}
}