I have like 3 hours trying to solve this simple problem. Here is what I am trying to accomplished: Ask the user to enter a number, and then add those numbers. If the users enters five numbers, then I should add five numbers.
Any help will be appreciated.
import java.util.Scanner;
public class loopingnumbersusingwhile
{
public static void main(String args[])
{
Scanner kb = new Scanner(System.in);
int input;
System.out.println("How Many Numbers You Want To Enter");
total = kb.nextInt();
while(input <= kb.nextInt())
{
input++;
System.out.println("How Many Numbers You Want To Enter" + input);
int input = kb.nextInt();
}
}
}
Your current code is trying to use input for too many purposes: The current number entered, the amount of numbers of entered, and is also trying to use total as both the sum of all numbers entered and the amount of numbers to be entered.
You'll want 4 separate variables to track these 4 separate values: how many numbers the user will entered, how many they entered so far, the current number they entered, and the total.
int total = 0; // The sum of all the numbers
System.out.println("How Many Numbers You Want To Enter");
int count = kb.nextInt(); // The amount of numbers that will be entered
for(int entered = 0; entered < count; total++)
{
int input = kb.nextInt(); // the current number inputted
total += input; // add that number to the sum
}
System.out.println("Total: " + total); // print out the sum
Add this code after you take how many numbers the user wants to add:
int total;
for(int i = 0; i < input; i--)
{
System.out.println("Type number: " + i);
int input = kb.nextInt();
total += input;
}
To print this just say:
System.out.println(total);
import java.util.Scanner;
public class LoopingNumbersUsingWhile
{
public static void main(String args[])
{
Scanner kb = new Scanner(System.in);
int input=0;
int total = 0;
System.out.println("How Many Numbers You Want To Enter");
int totalNumberOfInputs = kb.nextInt();
while(input < totalNumberOfInputs)
{
input++;
total += kb.nextInt();
}
System.out.println("Total: " +total);
}
}
You seem to be asking how many numbers twice.
public static void main(String args[])
{
Scanner kb = new Scanner(System.in);
System.out.println("How Many Numbers You Want To Enter");
int howMany = kb.nextInt();
int total = 0;
for (int i=1; i<=howMany; i++) {
System.out.println("Enter a number:");
total += kb.nextInt();
}
System.out.println("And the grand total is "+total);
}
What you should pay attention to:
name classes in CamelCase starting with a big letter
initialize total
don't initialize input twice
show an appropriate operand input request to your user
take care of your loop condition
don't use one variable for different purposes
which variable should hold your result?
how to do the actual calculation
Possible solution:
import java.util.Scanner;
public class LoopingNumbersUsingWhile {
public static void main(String args[]) {
Scanner kb = new Scanner(System.in);
System.out.println("How Many Numbers You Want To Enter: ");
int total = kb.nextInt();
int input = 0;
int sum = 0;
while (input < total) {
input++;
System.out.println("Enter " + input + ". Operand: ");
sum += kb.nextInt();
}
System.out.println("The sum is " + sum + ".");
}
}
Related
I'm trying to store the sum of 2 numbers inside a while loop so that once the loop ends multiple sums can be added up and given as a total sum, however I am rather new to Java and am not sure how to go about doing this.
I'm trying to use an array but I'm not sure if it is the correct thing to use. Any help would be greatly appreciated.
import java.util.Scanner;
public class StoredWhile{
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int TotalNum[]=new int[10];
Int Num1, Num2, AddedNum;
String answer;
do{
System.out.println("Please enter a number");
Num1 = input.nextInt();
System.out.println("Please enter a second number");
Num2 = input.nextInt();
AddedNum = Num1 + Num2;
System.out.println("The sum of the two entered numbers is " + AddedNum);
TotalNum[0]=AddedNum;
TotalNum[1]=;
System.out.println("Would you like to calculate the sum of two more numbers (y/n)?");
answer = input.next();
}
while (answer.equals("y"));
System.out.println("The total sum of all the numbers you entered is " + TotalNum);
}
}
There is a data container called ArrayList<>. It is dynamic and you can add as many sums as you need.
Your example could be implemented like this:
public class StoredWhile{
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
ArrayList<Integer> listOfSums = new ArrayList<>();
int Num1, Num2, AddedNum;
String answer;
do{
System.out.println("Please enter a number");
Num1 = input.nextInt();
System.out.println("Please enter a second number");
Num2 = input.nextInt();
AddedNum = Num1 + Num2;
System.out.println("The sum of the two entered numbers is " + AddedNum);
listOfSums.add(AddedNum);
System.out.println("Would you like to calculate the sum of two more numbers (y/n)?");
answer = input.next();
}
while (answer.equals("y"));
// Then you have to calculate the total sum at the end
int totalSum = 0;
for (int i = 0; i < listOfSums.size(); i++)
{
totalSum = totalSum + listOfSums.get(0);
}
System.out.println("The total sum of all the numbers you entered is " + totalSum);
}
}
From what I see, you come from a background of C# (Since I see capital letter naming on all variables). Try to follow the java standards with naming and all, it will help you integrate into the community and make your code more comprehensible for Java devs.
There are several ways to implement what you want, I tried to explain the easiest.
To learn more about ArrayList check this small tutorial.
Good luck!
Solution with array:
import java.util.Scanner;
public class StoredWhile{
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int TotalNum[]=new int[10];
int Num1, Num2, AddedNum;
String answer;
int count = 0;
do{
System.out.println("Please enter a number");
Num1 = input.nextInt();
System.out.println("Please enter a second number");
Num2 = input.nextInt();
AddedNum = Num1 + Num2;
System.out.println("The sum of the two entered numbers is " + AddedNum);
TotalNum[count]=AddedNum;
count++;
System.out.println("Would you like to calculate the sum of two more numbers (y/n)?");
answer = input.next();
}
while (answer.equals("y"));
int TotalSum = 0;
for(int i = 0; i <count; i++ ) {
TotalSum += TotalNum[i];
}
System.out.println("The total sum of all the numbers you entered is " + TotalSum);
}
}
This solution is not dynamic. There is risk that length of array defined on beginning will not be enough large.
I am learning Java and am having a very simple problem.
How to print the final sum from a while loop?
if I enter integers 10 10 40
the output I get is
10
20
60
but am only trying to get the final 60.
This answer can also relate to printing the final anything in a while loop as I just can't seem to get this.
my sample code below...
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
System.out.println("Enter a sequence of numbers to sum up: ");
double total = 0;
while (in.hasNextDouble()) {
double input = in.nextDouble();
total = total + input;
System.out.println("The Sum is: " + total);
}
}
Your main problem is that you have put the print statement inside the loop.
Also, in.hasNextDouble() doesn't make sense for input from the keyboard; it is useful when you are reading data from a file or a Scanner for some string. You can use an infinite loop (e.g. while(true){...}) and break it when there is no input from the user.
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
System.out.println("Enter a sequence of numbers to sum up, press Enter without any input to exit: ");
double total = 0;
while (true) {
String input = in.nextLine();
if (input.isBlank()) {
break;
}
total += Double.parseDouble(input);
}
System.out.println("The Sum is: " + total);
}
}
A sample run:
Enter a sequence of numbers to sum up, press Enter without any input to exit:
10
20
30
The Sum is: 60.0
A demo of a Scanner for a string:
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner("10 20 30");
double total = 0;
while (in.hasNextDouble()) {
double input = in.nextDouble();
total = total + input;
}
System.out.println("The Sum is: " + total);
}
}
Output:
The Sum is: 60.0
The problem lies in: System.out.println("The Sum is: " + total);
If you would like for only the final sum to be printed it needs to be outside of the while loop.
Please, print the total outside of the loop and it will work fine !
Code:
public class test {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
System.out.println("Enter a sequence of numbers to sum up: ");
double total = 0;
while (in.hasNextDouble()) {
double input = in.nextDouble();
total = total + input;
}
System.out.println("The Sum is: " + total);
}
I'm writing a java program to take a bunch of doubles the user inputs into the command line, add them together, and average them. The user can enter any amount of numbers. When they enter a negative number, the program does the adding/averaging. When i enter a number into cmd line it only lets me enter one. Can anyone help me improve this?
import java.util.Scanner;
public class Average
{
public static void main (String[] args)
{
Scanner keyboard = new Scanner(System.in);
System.out.println("Statistics Program, assignment one, program
Two. Sean Kerr");
System.out.println("\nPlease enter a series of numbers. To stop,
enter a negative number.");
//initialize two doubles and an int for our variables: the total numbers,
//the total added together, and the doubles the user enters into cmd line.
int amount = 0;
double totaladded = 0;
double userinput = 0;
userinput = keyboard.nextDouble();
while (userinput >= 0);
{
if(userinput > 0 )
{
totaladded = totaladded+userinput;
amount++;
}
}
System.out.println("Numbers entered: " + amount);
System.out.println("The average is: " + totaladded/amount);
}
}
use a do while loop instead,
public static void main (String[] args) {
Scanner keyboard = new Scanner(System.in);
int amount = 0;
double totaladded = 0;
double userinput = 0;
do {
System.out.println("Statistics Program, assignment one, program Two. Sean Kerr");
System.out.println("\nPlease enter a series of numbers. To stop, enter a negative number.");
//initialize two doubles and an int for our variables: the total numbers,
//the total added together, and the doubles the user enters into cmd line.
userinput = keyboard.nextDouble();
if(userinput > 0 ) {
totaladded += userinput;
amount++;
}
} while (userinput >= 0);
System.out.println("Numbers entered: " + amount);
System.out.println("The average is: " + totaladded/amount);
}
What I'm trying to make is an averaging program that takes any number of inputs. So far I need to have the user specify how many numbers they want to average, and if they don't give that many numbers the program crashes. Is there any way that I could just have them put as many numbers as they want and afterwards the array length is set?
Here is the code I am using right now:
import java.util.*;
public class Average_any
{
public static void main (String[] args) {
Scanner scan = new Scanner (System.in);
System.out.println ("How many numbers do you want to enter?");
final int ARRAY_LENGTH = scan.nextInt();
System.out.println ("Please type the numbers you want to find the average of, "
+ "and then type \"Done\".");
System.out.println ("Warning: Only type the exact amount of numbers that you specified.");
// If user doesn't enter same number, results in crash
double[] numbers = new double [ARRAY_LENGTH];
do {
for (int i = 0; i < numbers.length; i++) {
while (!scan.hasNextInt()) {
System.out.println("That's not a number!");
scan.next(); //Need this to enter another input
}
numbers[i] = scan.nextInt();
}
} while (!scan.hasNext("Done"));
double total = 0;
for (int i = 0; i < numbers.length; i++) {
total += numbers[i];
}
double average = total/ARRAY_LENGTH;
System.out.println ("Your average is: " + average);
}
}
(Just in case anyone is wondering, no this is not a school assignment, I was just wondering because we did a simpler version in school)
Take the array out of the equation altogether
Scanner scan = new Scanner (System.in);
double total = 0;
int count = 0;
while (scan.hasNextDouble()) {
total += scan.nextDouble();
count ++;
}
double average = total / count;
i apologize i know this looks simple but i'm kinda new to coding. the goal of the program is to take inputs from the user starting at index 0 and then save the inputs into the array. i'm probably close to solving this but i need some help.
here is the code:
public class ArrayTest
{
public static void main(String [] args)
{
Scanner input = new Scanner(System.in);
int numberOfGrades;
int counter = 0;
System.out.println("This program averages the grades you input.");
System.out.println("Please enter the number of grades you'd like averaged: ");
numberOfGrades = input.nextInt();
int[] grades = new int[numberOfGrades];
do
{
System.out.println("Please enter grade number " + (counter+1) + ": ");
grades[numberOfGrades] = input.nextInt();
counter++;
} while (counter < numberOfGrades);
System.out.println("The number of grades you wanted averaged was: " + grades.length);
}
}
Your logic is a bit off. numberOfGrades is the.. well.. number of grades. And when you do this: grades[numberOfGrades] = input.nextInt(); then you put the user's input in the grades array in location numberOfGrades, which you don't want.
What you do want is:
do {
System.out.println("Please enter grade number " + (counter+1) + ": ");
grades[counter] = input.nextInt();
counter++;
} while (counter < numberOfGrades);
This way, the array in location counter is accessed, and the user's input is placed inside it in the correct location.
Also, to calculate the average of the grades, like you are trying to do in the end of your program, you should do:
double sum = 0;
for (int grade : grades)
sum += grade;
And then your average will be:
average = 1.0d * sum / grades.length;
You can just as well put this summing logic inside your do-while loop and avoid the extra loop I introduced.
this instruction
grades[numberOfGrades] = input.nextInt();
must be replaced by
grades[counter] = input.nextInt();
try this ...
The thing that you were doing wrong is in the do while loop you were inserting value in the same array index grades[numberOfGrades] = input.nextInt(); should be replaced by grades[counter] = input.nextInt();
public class ArrayTest
{
public static void main(String [] args)
{
Scanner input = new Scanner(System.in);
int numberOfGrades;
int counter = 0;
System.out.println("This program averages the grades you input.");
System.out.println("Please enter the number of grades you'd like averaged: ");
numberOfGrades = input.nextInt();
int[] grades = new int[numberOfGrades];
do
{
System.out.println("Please enter grade number " + (counter+1) + ": ");
grades[counter] = input.nextInt();
counter++;
} while (counter < numberOfGrades);
System.out.println("The number of grades you wanted averaged was: " + grades.length);
}
}
You can try like this
public class ArrayTest {
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
System.out.println("enter number of elements");
int n=input.nextInt();
int arr[]=new int[n];
System.out.println("enter elements");
for(int i=0;i<n;i++){//for reading array
arr[i]=input.nextInt();
}
for(int i: arr){ //for printing array
System.out.println(i);
}
}