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How can I display the numbers in a for loop from 1-entered value?

So I am working on this homework problem called "pennies for pay" and I am basically done except for one issue. My for loop prints out the number of the inputted number that many times if that makes sense?
public class Assignment3 {
public static void main(String[] args) {
//INITIAL VARIABLES
int workdays;
double money;
double total = 0;
double add;
//GATHERING NUMBER OF DAYS WORKED
System.out.println("For how many days will the pay double? ");
Scanner a = new Scanner(System.in);
workdays = a.nextInt();
//PARTIAL OUTPUT
System.out.println("Day\t\tTotal Pay");
System.out.println("__________________________");
//FOR LOOP
for(int payday = 1; payday <= workdays;payday++){
money = Math.pow(2,payday - 1);
System.out.println(workdays +"\t$\t"+ money/100);
total = total + money/100;
}
//MORE OUTPUT
System.out.println("__________________________");
System.out.println("Total\t$\t" + total );
}
}
When I input 12 for days, the number 12 repeats itself 12 times. how can I get it to go from 1-12 please and thank you.

In your for loop you are printing the variable workdays in which it's value doesn't change inside the loop, that means it's constant.Since your target is to output pennies per day you should try this code if it helps
for(int payday = 1; payday <= workdays; payday++){
money = Math.pow(2,payday - 1);
System.out.println(payday + "\t$\t" + money/100);
total += money/100;
}

The value of workdays variable is always 12 if you input 12. In your System.out.println inside the loop, use payday instead of workdays. Because payday is the one being incremented for each iteration.
That should fix it.

Java programming: How do I make this for loop program that accepts user input subtract the input properly?

I am making a program that accepts user input to subtract all the numbers desired by the user
I first made the program ask how many numbers the user wants to subtract, and initialized the value in int inputNum, which is then passed on to the for loop for (int Count=1; Count<=inputNum; Count++), so that the program loops for user input, based on the inputNum.
Unfortunately, the output is wrong. I can't understand how this would work properly.
I've tried switching the operator in difference by making difference =- toBeSubtracted; into difference -= toBeSubtracted;
For difference =- toBeSubtracted;, here is a sample output
run:
How many numbers do you want to subtract?
2
Input numbers you want to subtract:
10
5
The difference of those numbers is -5
For difference -= toBeSubtracted;, here is a sample output
run:
How many numbers do you want to subtract?
2
Input numbers you want to subtract:
10
5
The difference of those numbers is -15
Here is the code:
import java.util.*;
public class ForLoops_Difference
{
public static void main(String[] args)
{
Scanner scan = new Scanner (System.in);
System.out.println("How many numbers do you want to subtract? ");
int inputNum = scan.nextInt();
int difference = 0;
System.out.println("Input numbers you want to subtract: ");
for (int Count = 1 ;Count<=inputNum; Count++)
{
int toBeSubtracted = scan.nextInt();
difference =- toBeSubtracted;
}
System.out.println("The difference of those numbers is " + difference);
}
}

Ok this might help you out:
difference = 0
and than you have:
difference -= toBesubtracted
so what you are doing is:
difference = difference - toBeSubtracted
which in terms is
difference = 0 - 10
difference = -10 - 5
thus you get -15
and where you have
difference =- toBeSubtracted
it is the same as
difference = -1 * toBeSubtracted
thus you get -5
I suppose you want output of 5. Here is your code with one change
import java.util.*;
public class ForLoops_Difference
{
public static void main(String[] args)
{
Scanner scan = new Scanner (System.in);
System.out.println("How many numbers do you want to subtract? ");
int inputNum = scan.nextInt();
int difference = scan.nextInt(); // so read in the first number here.
System.out.println("Input numbers you want to subtract: ");
for (int Count = 1;Count<inputNum; Count++) // go till from 1 to inputNum - 1 because you have already got one number above
{
int toBeSubtracted = scan.nextInt();
difference -= toBeSubtracted;
}
System.out.println("The difference of those numbers is " + difference);
}
}

You need to understand the operator shorthand notation. You should write -= for minus shorthand. The shorthand is equal to difference =difference - tobesubstracted. Since your initial value is 0 it becomes 0-10-5= -15.
Assign the first value as difference and then do the substraction of next values.
So something like:
difference = scanner.nextInt();
And then do the loop for rest of the values to minus from initial value.

The problem isn’t that your program is working incorrectly.
The problem is that the requirements are nonsense. You can have the difference between two numbers. The difference between 19 and 8 is 11. There is no such thing as the difference between 3 or more numbers. Therefore no program could ever produce that.
That said, Davis Herring is correct in the comment: there is no =- operator. You tried to use one in the line:
difference =- toBeSubtracted;
But the line is understood as just:
difference = -toBeSubtracted;
So your program just outputs the negative of the last entered number. I tried entering three numbers, 11, 3 and 5. The first time through the loop difference is set to -11. Next time this value is overwritten and -3 is set instead. In the final iteration the difference is set to -5, which “wins” and is output.
Instead I suggest that your program should always subtract 2 numbers, as you are also trying in your example. So the user needs not enter the number of numbers, but is just told to enter the two numbers. Then you also don’t need any loop. Just read the first number, read the second number, subtract the second from the first (or the first from the second, or the smaller from the larger, what you want) and print the result. I am leaving the coding to you to avoid spoiling it.

I did this
import java.util.*;
public class ForLoops_Difference
{
public static void main(String[] args)
{
Scanner scan = new Scanner (System.in);
System.out.println("How many numbers do you want to subtract? ");
int inputNum = scan.nextInt();
int difference = 0;
int currentNumber = 0; //current number from scanner
System.out.println("Input numbers you want to subtract: ");
for (int Count = 1 ;Count<=inputNum; Count++)
{
if(Count == 1)
{
//nothing to subtract if count is 1
currentNumber = scan.nextInt();
difference = currentNumber;
}
else {
currentNumber = scan.nextInt();
difference = difference - currentNumber;
}
}
System.out.println("The difference of those numbers is " + difference);
}
}
You started your difference at 0. So if you subtracted two numbers, 15 and 3, then you would get 0 - 15 - 3 = -18. I set the difference equal to the first number, 15 in the first loop. Then it should work correctly because you do 15 - 3 = 12.

Find the even sum and even max

I am trying to find the even sum and even max from numbers inputted by the user. For example, if they answered "How many integers?" with 4 and inputted the integers: 2, 9, 18, 4 it should output:
how many integers? 4
next integer? 2
next integer? 9
next integer? 18
next integer? 4
even sum = 24
even max = 18
Here is my code:
public static void evenSum(){
//prompt the user to enter the amount of integers
Scanner console = new Scanner(System.in);
System.out.print("how many integers? ");
int numbers = console.nextInt();
//prompt user to enter the first integer
System.out.print("next integer? ");
int firstNum = console.nextInt();
//set the even max to the firstNum
int evenMax = firstNum;
//set the evenSum to zero
int evenSum = 0;
//for loop for the number of times to ask user to input numbers
for (int i = 2; i <= numbers; i++) {
System.out.print("next integer? ");
int num = console.nextInt();
//check to see if the first number is even
if (firstNum % 2 == 0){
//if it is even then add it to the evenSum
evenSum += firstNum;
}
//check to see if the numbers entered are even
if (num % 2 == 0) {
//if they are even add them to the evenSum
evenSum += num;
}
//check to see if the number entered is bigger than the first number
if (num > firstNum) {
if (num % 2 == 0 ) {
evenMax = num;
}
}
}
System.out.println("even sum = " +evenSum);
System.out.println("even max = " +evenMax);
}
But here is what is my output is:
how many integers? 4
next integer? 2
next integer? 9
next integer? 18
next integer? 4
even sum = 28
even max = 4
Could someone help me figure out what the problem is?

You were doing some really weird stuff where the first time a number was entered it was treated as special. This was causing the first even number entered (2, in this case) to be added multiple times to the total.
Put all of your input in the same loop so you can treat everything equally:
public static void evenSum(){
//prompt the user to enter the amount of integers
Scanner console = new Scanner(System.in);
System.out.print("how many integers? ");
int numbers = console.nextInt();
int evenSum = 0;
int evenMax = 0;
//for loop for the number of times to ask user to input numbers
for (int i = 0; i < numbers; i++) {
//input new number
System.out.print("next integer? ");
int num = console.nextInt();
//check to see if the number is even. if it is not even,
//we don't care about it at all and just go to the next one
if (num % 2 == 0){
//add it to the sum
evenSum += num;
//if it's larger than the maximum, set the new maximum
if (num > evenMax) {
evenMax = num;
}
}
}
System.out.println("even sum = " +evenSum);
System.out.println("even max = " +evenMax);
}
As you can see, this code also only checks to see if a number is even once. There is no need to be continuously checking if num is even every time you use it: its value is not changing during the duration of a single run of the loop.

Move the following code inside the for loop to just before the for loop-
if (firstNum % 2 == 0){
//if it is even then add it to the evenSum
evenSum += firstNum;
}
This will prevent the repeated addition of the first number in the evenSum

You also want
if (num > evenMax) {
if (num % 2 == 0 ) {
evenMax = num;
}
}
or, alternatively
if (num > evenMax && num % 2 == 0) {
evenMax = num;
}
In your scenario, firstNum is 2 so every number after it is technically larger, so you will (theoretically) not get the largest even number entered after the first number.

Either move the first if condition inside the for loop upwards (outside of the for loop)
or store all of the user inputs in a data structure i.e. Array before processing them.
Storing them in Array would make it easier to manipulate the data.

Working code:-
Scanner console = new Scanner(System.in);
int numbers =0, firstNum =0, num =0 ;
System.out.print("how many integers? ");
numbers = console.nextInt();
System.out.print("next integer? ");
firstNum = console.nextInt();
int evenMax = 0;
int evenSum = 0;
if(firstNum%2==0)
{
evenSum = firstNum;
evenMax = firstNum;
}
for (int i = 1; i < numbers; i++) {
System.out.print("next integer? ");
num = console.nextInt();
if (num % 2 == 0) {
//don't add firstNum multiple times to the evenSum, earlier it was added every time you entered an even number
evenSum += num;
//check if the number you entered, i.e. num greater than the already existing greatest number i.e. evenMax and if so update it
evenMax = num > evenMax: num?evenMax;
}
}
System.out.println("even sum = " +evenSum);
System.out.println("even max = " +evenMax);
}
Hope this helps. There are three major problems in your code:-
The firstNum(if it's even) gets added to the sum every time you enter a even number. i.e. if first number is 4 and the loop runs 10 times and encounter 6 even numbers, then along with the even number 4 also gets added six times. If you want to use it as a special number and get it's value separately then you'll have to add it to the sum before the loop.
You should compare every new even number to the previous greatest even number and hence set the value of evenMax. You are comparing them to the firstNum so if the first number is 2 and the last even number is anything greater than two, it would be set as the value of evenMax. Compare every even number to the current maximum even number i.e current value of evenMax.
You don't check if the first number is evenor not and assign it to even max. So if it is 999999 it still get's assigned, but it is not even.
Please check it as correct answer and vote up if you find it useful.

Golf score program?

So I'm trying to make a program where it averages out your golf scores. I edited a standard averaging calculator to make it work:
import java.util.Scanner;
public class Test {
public static void main(String args[]){
Scanner input = new Scanner(System.in);
int total = 0;
int score;
int average;
int counter = 0;
while (counter >= 0){
score = input.nextInt();
total = total + score;
counter++;
}
average= total/10;
System.out.println("Your average score is "+ average);
}
}
But when I enter scores, I can keep entering infinite scores and it never averages them. It just keeps expecting another score. I know it has something to do with this line:
while (counter >= 0){
but I'm not sure what to do so it works right.

You never find a way to break out of the loop:
while (counter >= 0){
score = input.nextInt();
total = total + score;
counter++;
}
will loop 2 billion times (no I'm not exaggerating) since you don't have another way to break out.
What you probably want is to change your loop condition to this:
int score = 0;
while (score >= 0){
This will break out when a negative score is entered.
Also, you have an integer division at the end. You want to make floating-point, so change the declaration to this:
double average;
and change this line to this:
average = (double)total / 10.;

You need some way to beak out of the loop. For example, entering -1:
int score = input.nextInt();
if (score < 0) { break; }
total += score;
You also seem to have a couple of errors in the calculation of the average:
Don't always divide by 10 - use the value of counter.
Use floating point arithmetic. If you need an int, you probably want to round to nearest rather than truncate.
For example:
float average = total / (float)counter;

You have to specify the counter value, the default value is 0, so the condition in the while is always true, so you will go in an infinite loop.

while (true) {
score = input.nextInt();
if (score == 0) {
break;
}
total = total + score;
counter++;
}
Now your program will realize you're done entering scores when you enter the impossible score 0.

for loop structure

This program will calculate the average grade for 4 exams using a for loop by prompting
the user for exam grades, one at a time, then calculate the average and display the result.
public class ExamsFor4 {
public static void main(String[] arguments) {
int inputNumber; // One of the exams input by the user.
int sum = 0; // The sum of the exams.
int i; // Number of exams.
Double Avg; // The average of the exams.
TextIO.put("Please enter the first exam: "); // get the first exam.
inputNumber = TextIO.getlnInt();
for ( i = 1; i <= 4; i++ ) {
sum += inputNumber; // Add inputNumber to running sum.
TextIO.put("Please enter the next exam: "); // get the next exam.
inputNumber = TextIO.getlnInt();
if (i == 4) {
Avg = ((double)sum) / i;
TextIO.putln();
TextIO.putln("The total sum for all " + i +" exams is " + sum);
TextIO.putf("The average for the exams entered is %1.2f.\n", Avg);
break;
}
}
} // end main ()
} // end class ExamsFor4
My result:
Please enter the first exam: 100
Please enter the next exam: 99
Please enter the next exam: 98
Please enter the next exam: 97
Please enter the next exam: 96
The total sum for all 4 exams is 394
The average for the exams entered is 98.50.
This would be correct except for the last print out of: 'Please enter the next exam: 96'
I tried putting the IF statement between the 'sum' line and the TextIO.put 'Enter next exam', but that isolates it.
Thanks, from a Network Dude trap in a Programmer's world.

You have what is called an off-by-one error, compounded by the fact that you're convoluting your loop logic unnecessarily.
With regards to the loop, I recommend two things:
Don't loop for (int i = 1; i <= N; i++); it's atypical
Do for (int i = 0; i < N; i++); it's more typical
Instead of checking for the last iteration to do something, refactor and take it outside of the loop
Related questions
What is exactly the off-by-one errors in the while loop?
See also
Wikipedia/Off-by-one error
On Double Avg
In Java, variable names start with lowercase. Moreover, Double is a reference type, the box for the primitive double. Whenever possible, you should prefer double to Double
See also
Java Language Guide/Autoboxing
JLS 5.1.7 Boxing Conversion and 5.1.8 Unboxing Conversion
Effective Java 2nd Edition, Item 49: Prefer primitives to boxed primitives
Related questions
What is the difference between an int and an Integer in Java/C#?
Java: What’s the difference between autoboxing and casting?
Why does int num = Integer.getInteger(“123”) throw NullPointerException?
Why does autoboxing in Java allow me to have 3 possible values for a boolean?
Is it guaranteed that new Integer(i) == i in Java? (YES!!!)
When comparing two Integers in Java does auto-unboxing occur? (NO!!!)
Java noob: generics over objects only? (yes, unfortunately)
Rewrite
Here's a way to rewrite the code that makes it more readable. I used java.util.Scanner since I don't think TextIO is standard, but the essence remains the same.
import java.util.*;
public class ExamsFor4 {
public static void main(String[] arguments) {
Scanner sc = new Scanner(System.in);
final int NUM_EXAMS = 4;
int sum = 0;
for (int i = 0; i < NUM_EXAMS; i++) {
System.out.printf("Please enter the %s exam: ",
(i == 0) ? "first" : "next"
);
sum += sc.nextInt();
}
System.out.printf("Total is %d%n", sum);
System.out.printf("Average is %1.2f%n", ((double) sum) / NUM_EXAMS);
}
}
An example session is as follows:
Please enter the first exam: 4
Please enter the next exam: 5
Please enter the next exam: 7
Please enter the next exam: 9
Total is 25
Average is 6.25
Note that:
Only necessary variables are declared
The loop index is local only to the loop
There are no cluttering comments
Instead, focus on writing clear, concise, readable code
If it makes sense to make something final, do so
Constants in Java is all uppercase
Related questions
Why does (360 / 24) / 60 = 0 in Java
Because it performs integer division. This is why the cast to (double) prior to the division in above code is necessary, so that it performs floating point division.
How does the ternary operator work?
This is the ?: operator in above code, also known as the conditional operator.
See also: JLS 15.25 Conditional Operator ?:

Change your end condition to be strictly less than 4 and put the code that prints out the total and average outside the loop.

You should probably put the if-statment outside the for-loop. That way you don't need the if-statement. Second the statement in the loop should be < 4 instead of <= 4.
public class ExamsFor4 {
public static void main(String[] arguments) {
int inputNumber; // One of the exams input by the user.
int sum = 0; // The sum of the exams.
int i; // Number of exams.
Double Avg; // The average of the exams.
TextIO.put("Please enter the first exam: "); // get the first exam.
inputNumber = TextIO.getlnInt();
for ( i = 1; i < 4; i++ ) {
sum += inputNumber; // Add inputNumber to running sum.
TextIO.put("Please enter the next exam: "); // get the next exam.
inputNumber = TextIO.getlnInt();
}
Avg = ((double)sum) / i;
TextIO.putln();
TextIO.putln("The total sum for all " + i +" exams is " + sum);
TextIO.putf("The average for the exams entered is %1.2f.\n", Avg);
break;
} // end main ()
}

Just making few changes in your code makes it work. But you should follow cleaner approach as proposed in some of answers.
public class ExamsFor4 {
public static void main(String[] arguments) {
int inputNumber; // One of the exams input by the user.
int sum = 0; // The sum of the exams.
int i; // Number of exams.
double Avg; // The average of the exams.
TextIO.put("Please enter the first exam: "); // get the first exam.
inputNumber = TextIO.getlnInt();
sum += inputNumber;
for ( i = 1; i < 4; i++ ) {
TextIO.put("Please enter the next exam: "); // get the next exam.
inputNumber = TextIO.getlnInt();
sum += inputNumber; // Add inputNumber to running sum.
}
Avg = ((double)sum) / i;
TextIO.putln();
TextIO.putln("The total sum for all " + i +" exams is " + sum);
TextIO.putf("The average for the exams entered is %1.2f.\n", Avg);
} // end main ()
} // end class ExamsFor4

import java.util.Scanner;
public class ExamsFor4 {
public static void main(String[] arguments) {
int sum = 0; // The sum of the exams.
int i = 1; // Number of exams.
double avg = 0; // The average of the exams.
Scanner in = new Scanner(System.in);
System.out.print("Please enter the first exam: ");
sum += in.nextInt();
i++;
while(i<=4){
System.out.print("Please enter the next exam: ");
sum += in.nextInt();
if(i==4)
break;// this line is so that it wont increment an extra time.
i++;
}
System.out.println("The total sum for all " + i +" exams is " + sum);
avg = ((double)sum/i);
System.out.println("The average for the exams entered is" + avg);
} // end main ()
} // end class ExamsFor4