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using a while loop for user to input multiple int and find the max and min

so my homework question is prompt user a series of integers and find the max and min of those integer. Use a loop and -99 to break loop.Below is my code but my question is that is there a shorter way for this? feel free to comment and i appreciate your time reading this.
Scanner input=new Scanner(System.in);
int num1,num2,max,min;
System.out.print("enter a number: ");
num1=input.nextInt();
System.out.print("enter another number: ");
num2=input.nextInt();
max=Math.max(num1,num2);
min=Math.min(num1,num2);
while (num2!=-99){
System.out.print("enter a number or -99 to stop: ");
num2=input.nextInt();
if(num2!=-99){
max=Math.max(max,num2);
min=Math.min(min,num2);
}
}
System.out.println("largest is: "+max);
System.out.println("Smallest is: "+min);

You check for the condition of num2 != -99 twice, remember the first rule of programming, do not repeat yourself
You could save some lines by checking for min and max before asking for the next input. This way you do not need to check if num2 != -99 inside the while loop

Ok So after working on this. I finally did it. It does have a small bug, but I really don't wanna fix it so if anyway wants to edit this then be my guest.
Scanner input = new Scanner(System.in);
int studentNum = 0;
ArrayList<Integer> calc = new ArrayList<Integer>();
while (studentNum <= 100) {
System.out.print("Enter a number: ");
calc.add(input.nextInt());
studentNum += 1;
if (input.nextInt() == -99) {
break;
}
}
int min = Collections.min(calc);
int max = Collections.max(calc);
for (int i = 0; i < calc.size(); i++) {
int number = calc.get(i);
if (number < min)
min = number;
if (number > max)
max = number;
}
System.out.println("Max is " + max);
System.out.println("Min is " + min);
This does exactly what you want. However, there was a problem checking for the exit signal.
if (input.nextInt() == -99) {
break;
}
this checks if the userInput is equal to -99 then stops the program and calculates and prints out the min and max. However the tiny bug is that it will first ask for your number to add to the array list and then it will ask again for the userInput to check if its equal to -99. But overall it does exactly what you want.
Hope this helped.
EDIT I will work on it later and find a way to fix that bug if no one else knows.

Your code has one minor bug and can be slightly optimised. Things you might want to consider:
What happens (and what should happen) when the user types -99 as the second number?
Do you necessarily need to have at least 2 numbers? Wouldn't one be enough for the program to exit gracefully? The first number would then be both min and max.
Can you re-order your code lines so that the duplicated (num2!=-99) is not necessary anymore?
Pro questions:
What happens if the user types in some letters? How can you handle that case?
What happens if the user types in a super high number (bigger than the maximal integer)?
What happens if the user presses enter without typing any number?
Nitpicking:
Using + to concatenate strings and numbers is a bad idea because it's hard to remember where it works and where it doesn't.
Better look into String.valueOf(int i) and String.format(String format, Object... args)
Look up Google's Java Coding Style for formatting your code in best readable way. In many editors you can automatically apply the style. It describes things like where to use spaces or what to indent.

Java: Saving User Input to be Calculated in a Loop

Unfortunately, I can't attach my overall program (as it is not finished yet and still remains to be edited), so I will try my best to articulate my question.
Basically, I'm trying to take an integer inputted by the user to be saved and then added to the next integer inputted by the user (in a loop).
So far, I've tried just writing formulas to see how that would work, but that was a dead end. I need something that can "save" the integer entered by the user when it loops around again and that can be used in calculations.
Here is a breakdown of what I'm trying to make happen:
User inputs an integer (e.g. 3)
The integer is saved (I don't know how to do so and with what) (e.g. 3 is saved)
Loop (probably while) loops around again
User inputs an integer (e.g. 5)
The previously saved integer (3) is added to this newly inputted integer (5), giving a total of (3 + 5 =) 8.
And more inputting, saving, and adding...
As you can probably tell, I'm a beginner at Java. However, I do understand how to use scanner well enough and create various types of loops (such as while). I've heard that I can try using "var" to solve my problem, but I'm not sure how to apply "var". I know about numVar, but I think that's another thing entirely. Not to mention, I'd also like to see if there are any simpler solutions to my problem?

Okay So what you want is to store a number.
So consider storing it in a variable, say loopFor.
loopFor = 3
Now we again ask the user for the input.
and we add it to the loopFor variable.
So, we take the input using a scanner maybe, Anything can be used, Scanner is a better option for reading numbers.
Scanner scanner = new Scanner(System.in);//we create a Scanner object
int numToAdd = scanner.nextInt();//We use it's method to read the number.
So Wrapping it up.
int loopFor = 0;
Scanner scanner = new Scanner(System.in);//we create a Scanner object
do {
System.out.println("Enter a Number:");
int numToAdd = scanner.nextInt();//We use it's method to read the number.
loopFor += numToAdd;
} while (loopFor != 0);

You can just have a sum variable and add to it on each iteration:
public static void main(String[] args) {
// Create scanner for input
Scanner userInput = new Scanner(System.in);
int sum = 0;
System.out.println("Please enter a number (< 0 to quit): ");
int curInput = userInput.nextInt();
while (curInput >= 0) {
sum += curInput;
System.out.println("Your total so far is " + sum);
System.out.println("Please enter a number (< 0 to quit): ");
}
}

You will want to implement a model-view-controller (mvc) pattern to handle this. Assuming that you are doing a pure Java application and not a web based application look at the Oracle Java Swing Tutorial to learn how to build your view and controller.
Your model class is very simple. I would suggest just making a property on your controller that is a Java ArrayList of integers eg at the top of your controller
private Array<Integer> numbers = new ArrayList<Integer>();
Then your controller could have a public method to add a number and calculate the total
public void addInteger(Integer i) {
numbers.addObject(i);
}
public Integer computeTotal() {
Integer total = 0;
for (Integer x : numbers) {
total += x;
}
return total;
}

// This will keep track of the sum
int sum = 0;
// This will keep track of when the loop will exit
boolean errorHappened = false;
do
{
try
{
// Created to be able to readLine() from the console.
// import java.io.* required.
BufferedReader bufferReader = new BufferedReader(new InputStreamReader(System.in));
// The new value is read. If it reads an invalid input
// it will throw an Exception
int value = Integer.parseInt(bufferReader.readLine());
// This is equivalent to sum = sum + value
sum += value;
}
// I highly discourage the use Exception but, for this case should suffice.
// As far as I can tell, only IOE and NFE should be caught here.
catch (Exception e)
{
errorHappened = true;
}
} while(!errorHappened);

How to solve this program?

I found this Java exercise :
Create a class Sales that has TotalSales (double) , Commission (double),
Commissi onRate (double), and NoOfItems (integer).
write a java application that asks the user to enter the Total Sales and the number of items then calculates the commission and prints it out.
The commission rate should be as following:
Condition :
Less than 500, commissionRate is 0
Greater than or equal 500 or Number of Items >= 5, commission rate is 5%.
Grater than or equal 1000 or Number of items >=10, commission rate is 10%
..
I wrote this code:
Main Class :
import java.util.Scanner;
public class testSales {
public static void main(String[] args) {
Sales s1 = new Sales();
Scanner get = new Scanner(System.in);
System.out.println("Enter total Sales");
s1.totalSale = get.nextDouble();
System.out.println("Enter number of Items");
s1.NoOfItems = get.nextInt();
if(s1.totalSale < 500){
s1.commission = s1.commissionRate = 0;
}
else if(s1.totalSale >= 500 && s1.totalSale <= 999 || s1.NoOfItems >= 5 && s1.NoOfItems <=9){
s1.commission = s1.commissionRate = s1.totalSale * 5 / 100;
}else if(s1.totalSale >= 1000 || s1.NoOfItems >=10) {
s1.commission = s1.commissionRate = s1.totalSale *10/100;
}
System.out.println(s1.commission);
}
}

One problem in your code is the case where NoOfItems > 5 but totalSale < 500. For this case, the commission will incorrectly be set to 0 because the first if statement eats it.
Please try to be more specific with your question. "this doesn't work and I don't know why" is not easy to help with.

Aside from the point brought up by HedonicHedgehog, there are a few other things to consider:
The sales class only has two global variables, which corresponds to the information entered by the user. The other two fields, commission and commissionRate, are calculated values. Therefore, there is no need to create variables for them. Just add to the sales class accessor methods (getters) that return these values. For example, below is my getCommission() method:
public double getCommission()
{
return totalSales * getCommissionRate();
}
Of course, you can see this method is dependent upon the getCommissionRate() method. Because there is a gap on your requirements with total items, I am ignoring it for now:
public double getCommissionRate()
{
if (totalSales < 500)
return 0;
if(totalSales < 1000)
return .05;
else
return 0.1;
}
Alternatively, you could create a LOCAL commission variable, and set the value before returning it. It is a good programming practice to limit the scope of your variables. In this case, there is not a good reason to have a global commission or commissionRate variables.
Lastly, your test class is simplified because all you need to do is to prompt the user for the two needed fields, and it simply spits out the output because the Sales class provides the calculation needed to figure out the rest:
public static void main(String[] args)
{
Sales s1 = new Sales();
Scanner input = new Scanner(System.in);
System.out.print("Enter total Sales");
s1.setTotalSales(input.nextDouble());
System.out.print("Enter number of Items: ");
s1.setNumOfItems(input.nextInt());
System.out.printf("$%.2f", s1.getCommission());
input.close();
}
I used the printf() method to format the output string. The following is a sample run:
Enter total Sales: 503.45
Enter number of Items: 5
$25.17
Enter total Sales: 1003.67
Enter number of Items: 19
$100.37
Enter total Sales: 45.00
Enter number of Items: 19
$0.00
Remember that this example ignores the number of items because of the reasons already mentioned. Once you figure out what needs to be done to cover of the gap in the requirements, you can modify this code to do the rest. Also remember that your Sales class only requires two fields: totalSales and numOfItems. The other to components (commission, and commissionRate) are calculated; therefore, no global variable or setter methods needed. Just the two getter methods I provided.

Debugging School Project

Right, I am working on a program for school the purpose of the program is to find the minimum number of coins, I am a novice programmer and this is my first time so I dont know the thousands of other things and what not other people do. I wrote the code and it works, but I seem to have found a bug/glitch or w/e you want to call it.
my code
import java.util.Scanner;
public class Coin {
public static void main (String[] Args) {
int quarters = 25;
int dimes = 10;
int nickles = 5;
int pennies = 1;
System.out.println("Enter in a number between 1-99");
// "Input" Part of Code (Remember this and go back for reference)
Scanner Userinput = new Scanner(System.in);
int stuff = Userinput.nextInt();
int q = stuff/quarters;
String A = "Number of Quarters:" +q;
System.out.println(A);
int hold = stuff%quarters;
int d = hold/dimes;
String B = "Number of Dimes:" +d;
System.out.println(B);
int hold1 = stuff%dimes;
int n = hold1/nickles;
String C = "Number of Nickles:" +n;
System.out.println(C);
int hold2 = stuff%nickles;
int p = hold2/pennies;
String D = "Number of Pennies:" +p;
System.out.println(D);
System.out.println("Thank you for Using My Program");
}
}
Now, everything works fine I can input any number I like and get the desired result, however for some odd reason I cannot fathom I type in any number between 75-79 and there is an added Nickle for some odd reason and I have spent the better part of 2 hours trying to figure out exactly what is wrong but cannot. Hav tried dozens of toher numbers and they work fine except for that one little area.
Can someone tell me by chance what might be wrong?

Your hold = ... lines should be based on the previous hold value rather than the full amount (stuff).
int hold2 = hold%nickles;

You need to subtract off what has already been accounted for when adding previous, larger coins.
For example, if I say 77, then the program will check 77%10 and return 7. You would want to adjust your "stuff" value by any previously added coins. So in this case, after adding 3 quarters (75) we would want to set stuff = stuff - 75 (stuff -= 75).
EDIT: to be more precise, after every calculation you could run
stuff -= q * quarters;
of course, changing the variables to be appropriate for each part of your code.

Java method passing/ordered logic inquiry

Let me first make it clear that this is for an assignment. I'm very new to programming so all guidance is greatly appreciated. The program I have to calculate is a parking fee charge for a $2.00 minimum for 3 hrs or less, .50 cents per additional hr, and charge is capped at $10/ per 24 hr period. Program must display most recent customer charge as well as running total. Constants must be initialized, Math.ceil must be used, and method calculateCharges must be used to solve each cust's charge. I get uber errors when I attempt to run this program, and you'll probably laugh when you see it, but where have I erred? I'm not looking for the answer to be handed to me, just looking for the logic behind how to get to the correctly written program. Please help!
package Parking;
import java.util.Scanner;
public class parking
{
private static final double THREE_HOURS = 2.00;
private static final double PER_HOUR_COST = .50;
private static final double WHOLE_DAY_COST = 10.00;
public static void main (String [] args)
{
double hoursParked = 0;
double cumulativeCharges = 0;
double storage1 = 0;
double storage2 = 0;
Scanner input = new Scanner(System.in);
System.out.print("\nThis program displays the charge for the most recent customer");
System.out.print(" as well as the running total of yesterday's receipts\n");
do
{ System.out.printf("Enter an number between 1-24 for hours parked in garage or -1 to quit:");
hoursParked = input.nextDouble ();
}
while((hoursParked > 0)&&(hoursParked <= 24)&&(hoursParked != -1));
if( hoursParked <= 3)
System.out.printf("Most recent customer's charge was: %.2f\n" , THREE_HOURS);
storage1 += THREE_HOURS;
if(hoursParked >= 18.01)
System.out.printf("Most recent customer's charge was:%.2f\n" , WHOLE_DAY_COST);
storage2 += WHOLE_DAY_COST;
double result = calculateCharges(hoursParked * PER_HOUR_COST);
System.out.printf("Most recent customer charge was:%.2f\n" , result);
cumulativeCharges = storage1 + storage2;
System.out.printf("Running total of yesterday's receipts is:%.2f\n" , cumulativeCharges);
} // end main
public static double calculateCharges (double hoursParked)
{
Math.ceil(hoursParked);
double total = hoursParked * PER_HOUR_COST;
return total;
} // end method calculateCharges
} // end class parking

In your while condition, the third condition is useless because if the value is positive, that necessarily means it is different than -1.
In your function you want to calculate the cost of parking time but you give as parameter a cost instead of a number of hours when you call your function. Is that normal? With that you will calculate the cost of the cost instead of the cost corresponding to a number of hours.
public static double calculateCharges (double hoursParked)
and
double result = calculateCharges(hoursParked * PER_HOUR_COST);

There's a couple things here.
Your while condition is checked at the end of the do loop, it is what allows you to break after reading hoursParked. Thus, the only way you are going to reach the code outside of the do loop (after the while), is if hoursParked is -1.
Secondly, when you do not have braces for your if conditions, you are only executing the first line after it, aka. the System.out.print's. Therefore, your first if condition will execute (printing the string), then storing 2.00 in storage1. Similarly, the second if condition will execute (printing the string), then storing 10.00 in storage2.
Because hoursParked is always -1, you are passing in (-1 * .5) to calculateCharges. You are not storing the result of Math.ceil() so it effectively does nothing. You are then returning (-.5 * .5) = -.25.
cumulativeCharges is just adding 2 + 10 in every case.
Suggestions - make sure you are encapsulating the code you want to execute inside the do loop, and only break after you have done your calculations on hoursParked.