[tut] Calculating average (not GUI)

Code:

public class Average {
    
    public static void main(String[] args) {
    	
    	int first = 5;
    	int second = 7;
    	int third = 3;
    	
    	double avg = (first + second + third)/3;
    	
    		System.out.print(avg);
    	

    }
}

The first 3 lines of code for main are declaring 3 integers, which equal different numbers. These will be the 3 numbers used in the average calculation. Then, the 4th line is the double (decimal number) that the average will be, so in this case it's all the integers (ints) added together and divided by 3 (the number of ints). Then, they are printed out.

 

What if I want to take an average of non ints! Give it user input when its running... It would be better that way.

 

I'm still learning Java myself and haven't learned how to do that yet

 

Code:

import java.util.*;


public class Average 
{

	static Scanner s = new Scanner(System.in);

	public static void main(String[] args) 
	{

		System.out.print("Enter 1rst int:");
		int first = s.nextInt();
		System.out.print("Enter 2nd int:");
		int second = s.nextInt();
		System.out.print("Enter 3rd int");
		int third = s.nextInt();

		double avg = (first + second + third) / 3;

		System.out.print(avg);

	}
}

There ya go. You need to use a scanner to do it.

s.nextInt(); looks for an int input, and if its not an int it throws an error.

Here is a method that stops the error. D:

Code:

public static int getInput(String output) 
	{
		while (true) 
		{
			try 
			{
			System.out.print(output);
			return s.nextInt();
			} 
			catch (InputMismatchException e) 
			{
				s.next();
			}
		}

	}

the parameter is what text you want displayed like "Enter int A:" It basicly looks for the error which is if you put the wrong input in, if it finds it, the program exacutes the catch statement which takes the next input what ever it is, then the while loops jumps back to the start and begins again until it can get out threw the return statement. To use my method, do this

Code:

int first = getInput("Enter A:");

Hope you learned something.

 

SuF, I ran your code and it didn't work.
Do I have to import something or what?
It said: Cannot find symbol Scanner.
Thanks.


EDIT: Haha, of course, just added import java.util.*; and it worked.. my bad.. , your bad too! Hehe.

 

fuck, forgot to put the import... thought i had...

 

Code:

public class Average {
    
    public static void main(String[] args) {
	
	static Scanner s = new Scanner(System.in);
	
	int ctr=0;
	double avg=0;
	for (int ctr=0; ; ctr++)
    	{
		System.out.print("Enter int #" + ctr + ":");

		try {avg+= s.nextInt();}
		catch (InputMismatchException e) 
		{break;}
	}
    	
	System.out.print(avg/ctr);
    	

    }
}

would this work? havent done java in forever (downloading eclipse right now ^^ only 10 hours left)