So the code posted works and seems to give correct values. The only problem is that it prints every line in the loop instead of just the answer. How can I make it just print the answer instead of every line leading up to it?
import java.util.Scanner;
public class CountLoop{
public static void main (String[] args){
Scanner in = new Scanner (System.in);
int i = -1;
int limit = 0;
System.out.println("Please enter a number");
String end1 = in.nextLine();
int end = Integer.parseInt(end1);
while (i < end){
i++;
limit = (i + limit);
System.out.println("The sum of the numbers in between 0 and " + end + " is i = " + limit);
}
}
}
I'm fine with using other types of loops as well, as I'll need to show an example with all the different types of loops being used anyway, so any help is appreciated.
Move your system.out.println outside of your while loop
while (i < end){
i++;
limit = (i + limit);
}
System.out.println("The sum of the numbers in between 0 and " + end + " is i = " + limit);
Or the modern version in Java 8:
int sum = IntStream.range(startInclusive,endExclusive).sum();
System.out.println("The sum of the numbers in between " + startInclusive +
" and " + (endExclusive -1) + " is sum = " + sum);
Renamed variables ;-)
limit -> sum
0 -> startInclusive
end -> endExclusive - 1
Related
First of all here is my code
import java.util.Scanner;
public class Pengulangan {
public static void main(String[] args) {
Scanner sc = new Scanner (System.in);
int i, number, line, total;
int even, b = 0;
double rat;
System.out.print("Input number: ");
number = sc.nextInt();
even = number/2;
System.out.print("Total sum of number from 1 to number " + number + " is " + even + "\n");
i = 2;
line = 1;
while (i <= number) {
System.out.println("Even number-" + line + " is " +i);
line = line+1;
i = i +2;
}
total = ((number/2) * (even+1));
System.out.printf("Total sum of even number from the number " + number + " = " + total + "\n");
rat = 2*(total/number);
System.out.printf("Sum of average number from the number " + number + " = " + rat + "\n");
}
}
On this specific line on top of the second S.O.P
even = number/2;
i would like to put a loop there to find out how many Even numbers are on the input (ex- 10)
So i tried this code
int i = 1;
while (i <= number) {
if (i%2 == 0)
even = even + 1;
else
odd = odd + 1; //Not going to use this..
i++;
}
System.out.println("Total sum of even number is : ")
I tried putting that code in but i can't make it work, i tried it myself with only the code above and the results are exactly what im looking for but i can't put that in my first code ( the top one ), so i ended up using a sneaky way to get the even numbers.
I need help putting that total sum code to my main code
Sounds like a homework. You don't need loops or anything fancy, if you just want to get the sum of even numbers up to the number you input. Let n be the input number from your program and
class Main {
public static void main(String[] args) {
int n = 10;
//This is the math forumla
int total_sum_math = (((n/2)*((n/2)+1)));
System.out.println("Total sum of even number is : "+total_sum_math+"");
}
}
Reference: https://math.stackexchange.com/questions/3285727/sum-of-even-numbers-n
Where the commented section is, it says that there is a StackOverflowError - null. I am trying to get it to make random numbers to match up with an inputted value. The goal of this code is to do the following:
Accept a top number (ie 1000 in order to have a scale of (1-1000)).
Accept an input as the number for the computer to guess.
Computer randomly guesses the first number and checks to see if it is correct.
If it is not correct, it should go through a loop and randomly guess numbers, adding them to an ArrayList, until it guesses the input. It should check to see if the guess is already in the array and will generate another random number until it makes one that isn't in the list.
In the end, it will print out the amount of iterations with the count variable.
Code:
import java.util.*;
public class ArrNumGuess
{
public static Integer top, input, guess, count;
public static ArrayList <Integer> nums;
public static void main ()
{
System.out.println("Please enter the top number");
top = (new Scanner(System.in)).nextInt();
System.out.println("Please enter the number to guess (1 - " + top + ")");
input = Integer.parseInt(((new Scanner(System.in)).nextLine()).trim());
nums = new ArrayList<Integer>(); //use nums.contains(guess);
guess = (new Random()).nextInt(top) + 1;
nums.add(guess);
System.out.println("My first guess is " + guess);
count = 1;
if(guess != input)
{
guesser();
}
System.out.println("It took me " + count + " tries to find " + guess + " and " + input);
}
public static void guesser()
{
boolean check = false;
while(!check)
{
guess = (new Random()).nextInt(top) + 1; //Stack Overflow - null
if(nums.contains(guess) && !(guess.equals(input)))
{
count--;
guesser();
}
else if(guess.equals(input))
{
check = true;
System.out.println("My guess was " + guess);
// nums.add(guess);
count++;
}
else
{
System.out.println("My guess was " + guess);
nums.add(guess);
count++;
}
}
}
}
In guesser() method, you're invoking itself:
if(nums.contains(guess) && !(guess.equals(input)))
{
count--;
guesser();
}
There is quite a possibility it will never end. But all that is in while loop, so why not get rid of recurrence and do this in an iterative style?
OK - a different approach to your guesser for fun. Enumerate a randomized sequence of numbers in specified range (1 to 'top') and find the guess in the list whose index is effectively the number of "attempts" and return.
(BTW - #Andronicus answer is the correct one.)
/** Pass in 'guess' to find and 'top' limit of numbers and return number of guesses. */
public static int guesser(int guess, int top) {
List<Integer> myNums;
Collections.shuffle((myNums = IntStream.rangeClosed(1, top).boxed().collect(Collectors.toList())), new Random(System.currentTimeMillis()));
return myNums.indexOf(guess);
}
You are making it more complicated than it needs to be and introducing recursion unnecessarily. The recursion is the source of your stack overflow as it gets too deep before it "guesses" correctly.
There is a lot of sloppiness in there as well. Here's a cleaned up version:
import java.util.*;
public class Guess {
public static void main(String args[]) {
System.out.println("Please enter the top number");
Scanner scanner = new Scanner(System.in);
int top = scanner.nextInt();
System.out.println("Please enter the number to guess (1 - " + top + ")");
int input = scanner.nextInt();
if (input < 1 || input > top) {
System.out.println("That's not in range. Aborting.");
return;
}
ArrayList <Integer> nums = new ArrayList<>();
Random rng = new Random(System.currentTimeMillis());
while(true) {
int guess = rng.nextInt(top) + 1;
if (!nums.contains(guess)) {
nums.add(guess);
if (nums.size() == 1) {
System.out.println("My first guess is " + guess);
} else {
System.out.println("My guess was " + guess);
}
if (guess == input) {
System.out.println("It took me " + nums.size() + " tries to find " + guess);
break;
}
}
}
}
}
Our professor gave us a list of 982 numbers in a text file and we have read text from the file and print out some info about the numbers. I have everything correct so far, (she gave us the correct answers), except the total of the odd numbers. I can't figure out how to get the average of the odd numbers which is 48201.56.
I keep getting the result 97354, which is weird because I'm following the same method I used to find the average of all the numbers and the average of the even numbers.
import java.io.*;
import java.util.*;
public class Homework1sem2
{
public static void main(String args[]) throws IOException
{
System.out.println("Student name: Ethan Creveling "
+ "\nEmail: ec904066#wcupa.edu");
double f = 0;
double e = 0;
double d = 0;
int c = 0;
int b = 0;
int a = 0;
File myFile = new File("numbers.txt");
Scanner inputFile = new Scanner(myFile);
while (inputFile.hasNext())
{
int i = inputFile.nextInt();
a++;
d += i;
if(i%2 == 0)
{
b++;
e += i;
}
else
c++;
f += i;
}
System.out.println("Total number: " + a);
System.out.println("Total even number: " + b);
System.out.println("Total odd number: " + c);
System.out.println("Total average: " + d/a);
System.out.println("Total even average: " +e/b);
System.out.println("Total odd average: " + f/c);
}
}
I would like to know why the answer for "Total odd average" isn't 48201.56. Thanks
Your else statement is only performing the c++; operation.
Wrap it in brackets like this:
else {
c++;
f += i;
}
f += i; is being performed outside of the else statement which means that it is being called on every loop of the while. If you check your values, you should find that both f and d are the same value.
If you encapsulate your else statement as follows, this should fix the problem
else {
c++;
f += i;
}
I'm trying to create a program that takes each number typed in by the user and sort them out as even, odd and the number zero values.
The result should look like something like this:
User Input: 14005
Output:
Even Numbers: 4
Odd Numbers: 1, 5
Zero's: 0, 0
This is the code I've written, I thought of using string concatination in order to add a new value each time the loop checks for the next character, don't know whether I'm thinking right or not though, would appriciate if someone could tell me where I'm thinking in the wrong way.
package com.craydesign;
import javax.swing.JOptionPane;
public class Main {
public static void main(String[] args) {
String number = JOptionPane.showInputDialog("Please enter a number: ");
String evenNumbers = "";
String oddNumbers = "";
String numberZero = "";
for(int i = 0; i < number.length(); i++) {
if(number.charAt(i) % 2 == 0) {
evenNumbers.concat(Integer.toString(i) + ", ");
} else if(number.charAt(i) % 2 != 0) {
oddNumbers.concat(Integer.toString(i) + ", ");
} else if (number.charAt(i) == 0){
numberZero.concat(Integer.toString(i) + ", ");
}
}
JOptionPane.showMessageDialog(null, "Even numbers: " + evenNumbers + "\n" + "Odd numbers: " + oddNumbers + "\n" + "Zero's: " + numberZero);
}
}
use Character.getNumericValue() instead of charAt(i)
public static void main(String[] args) throws IOException
{
String number = JOptionPane.showInputDialog("Please enter a number: ");
StringBuffer evenNumbers = new StringBuffer();
StringBuffer oddNumbers =new StringBuffer();
StringBuffer numberZero =new StringBuffer();
for(int i = 0; i < number.length(); i++) {
int value=Character.getNumericValue(number.charAt(i));
if(value!=0 && value % 2 == 0) {
evenNumbers.append(value).append(',');
} else if(value % 2 != 0) {
oddNumbers.append(value).append(',');
} else if (value == 0){
numberZero.append(value).append(',');
}
}
JOptionPane.showMessageDialog(null, "Even numbers: " + evenNumbers + "\n" + "Odd numbers: " + oddNumbers + "\n" + "Zero's: " + numberZero);
}
EDIT:(displaying numbers in sorted order)
String evenNo[]=evenNumbers.toString().split(",");
String oddNo[]=oddNumbers.toString().split(",");
Arrays.sort(evenNo);
Arrays.sort(oddNo);
JOptionPane.showMessageDialog(null, "Even numbers: " + Arrays.toString(evenNo) + "\n" + "Odd numbers: " + Arrays.toString(oddNo) + "\n" + "Zero's: " + Arrays.toString(numberZero.toString().substring(0,
numberZero.length()-1).split(",")));
You are using String for output and appending the output in the string.
Its a bad idea. as String class is immutable so if you do change anything in String it will create a new Object in memory.
So your solution will take extra memory.
Accroding to me you can solve this problem in two ways
Use StringBuffer class instead of String class for appending
Use ArrayList to Store your result. and iterate over the arraylist and show the output as you want.
Thanks,
Aman
I need to display an output like this:
Enter an integer: 3
Number Squared Cubed
====== ======= =====
1 1 1
2 4 8
3 9 27
But instead, when I run the code, I get this output:
Number Squared Cubed
====== ======= =====
3 9 27
In other words, I need to display the powers of an integer,including the powers of the numbers less than or equal to the integer. The numbers of the lesser integers need to be listed but are not displayed along with the integer being entered. How do I fix the code to make sure it outputs all of the integers that are less than or equal to the integer being entered? There are no errors (i.e. red exclamation mark circles) but I need to figure out the proper calculation.
Here is the code:
====================
import java.util.Scanner;
public class Powers
{
public static void main(String[] args)
{
System.out.println("Welcome to the Squares and Cubes Table");
System.out.println();
Scanner sc = new Scanner(System.in);
String choice = "y";
while(choice.equalsIgnoreCase("y"))
{
// get the input from the user
System.out.println("Enter an Integer: ");
int integerNext = sc.nextInt();
System.out.println("Number" + " " + "Squared" + " " + "Cubed");
System.out.println("======" + " " + "======" + " " + "======");
for(int i = 1; i <= integerNext; i++)
{
i = integerNext;
int numberSquared = (int) Math.pow(i, 2);
int numberCubed = (int) Math.pow (i, 3);
String message = "\n" + i + " " + numberSquared + " " + numberCubed;
System.out.println(message);
System.out.println();
// see if the user wants to continue
System.out.print("Continue? (y/n): ");
choice = sc.next();
System.out.println();
}
}
}
}
Help is always appreciated. Thanks.
Firstly, as Nikhil said: "Remove the line i = integerNext; It is resetting the value of I and therefore only last row is printed".
Secondly, move the first closing curly brace to before getting user input - you want to run the loop, and only ask about continuing when that's finished, if I understand correctly.
Remove the line i = integerNext; It is resetting the value of I and therefore only last row is printed
Your are almost there. Since you are looping from 1 to integerNext (which is 3 in your text), the looping variable i will get the values [1,2,3] each iteration, so you don't have to set i manually. When you do:
i = integerNext;
you are setting i to 3, so the loop will finish when it reaches the loop condition.
You may also want to put the "Continue?" check outside the loop:
for (int i = 1; i <= integerNext; i++) {
int numberSquared = (int) Math.pow(i, 2);
int numberCubed = (int) Math.pow(i, 3);
String message = "\n" + i + " " + numberSquared + " " + numberCubed;
System.out.print(message);
}
// see if the user wants to continue
System.out.print("\nContinue? (y/n): ");
choice = sc.next();
System.out.println();
import java.util.Scanner;
public class SquaresAndCubes {
public static void main(String[] args)
{
// Welcome the user
System.out.println("Welcome to the Squares and Cubes table");
System.out.println();
Scanner sc = new Scanner(System.in);
String choice = "y";
do
{
// Get input from the user
System.out.print("Enter an integer: ");
int integer = sc.nextInt();
// Create a header
String header = "Number " + "Squared " + "Cubed " + "\n"
+ "====== " + "======= " + "===== ";
System.out.println(header);
int square = 0;
int cube = 0;
String row = "";
for (int i = 1; i <= integer; i++)
{
square = i * i;
cube = i * i * i;
row = i + " " + square + " " + cube;
System.out.println(row);
}
// See if the user wants to continue
System.out.print("Continue? (y/n): ");
choice = sc.next();
System.out.println();
}
while (!choice.equalsIgnoreCase("n"));
}
}
Basic way to do it with foor loop and some printlines
Scanner sc = new Scanner(System.in);
System.out.print("What number would you like to go up to? ");
int userInt = sc.nextInt();
System.out.println("");
System.out.println("Here is your table!");
System.out.println("");
System.out.println("number | squared | cubed");
System.out.println("------ | ------- | -----");
for (int i = 1; i <= userInt; i++){
System.out.println(i + " | " + (i * i) + " |" + " " +(i * i * i));
}