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Thread: Help with while loop

  1. #1
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    Default Help with while loop

    I am trying to write a program that takes an int as input. Then it prints out the number with spaces and the sum. Example:

    input: 123
    output: 1 2 3 The sum is: 6


    here is the output I am getting: 1 The sum is: 6

    here is my code
    import java.util.*;
     
    public class ch5PrEx1
    {
    	static Scanner console = new Scanner(System.in);
     
    	public static void main(String[] args)
    	{
    	  String input;
    	  int sum = 0, numericInput, length;
     
    	  System.out.println("Please enter an integer: ");
    	  System.out.println();
     
    	  input = console.next();
    	  numericInput = Integer.parseInt(input);
    	  numericInput = Math.abs(numericInput);
    	  input = Integer.toString(numericInput);
     
    	  length = input.length();
     
     
    	  System.out.println(input.charAt(length-length) + " " + Addition(length, input) + " " + "The sum is: " + Sum(sum, length, numericInput));
     
     
     
    	}
     
    	public static int Sum(int sum, int length, int numericInput)
    	{
    		int counter = 0;
    		while(counter < length)
    		{
     
    			sum += numericInput % 10;
    			numericInput /= 10;
    			counter = counter + 1;
    		}
     
    		return sum;	
    	}
     
    	public static String Addition(int length, String input)
    	{
    		String output = " ", index; 
    		int add = 0, counter = 0;
     
     
     
    		while(counter < length)
    		{
    			index = input.substring(add + 1, add + 1);
    			output = String.format("%s", index);
    			add = add + 1;
    			counter++;
     
     
    		}
     
    		return output;
     
     
     
    	}
     
    }

    Thanks in advance!


  2. #2
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    Default Re: Help with while loop

    Quote Originally Posted by mwr76 View Post
    System.out.println(input.charAt(length-length) + " " + Addition(length, input) + " " + "The sum is: " + Sum(sum, length, numericInput));
    IF you look at the first thing you put in this Print statement:
    "input.charAt(length-length)" -> no matter the value of length, the value of "length-length" will be 0.

    Therefore, you will print out the String's Index of 0, which will always be the first number. In order to print out all of the values, you will need a method to do so...
    Simplicity calls for Complexity. Think about it.

  3. #3
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    Default Re: Help with while loop

    I do have a method to do that Addition(). I want it to print the index at 0 first then print the rest of the indexes. Which the Addition methods does, except it only returns the last value.

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    Default Re: Help with while loop

    Addition() (that's a bad name for a Java method - follow the convention in the API - you should be using a lowerCaseFirstLetter()) uses String.subtring(int, int) where both ints are the same. Read the API doc for that method - particularly the bit around
    Thus the length of the substring

  5. #5
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    Default Re: Help with while loop

    Here's a tip:

    Your output is this (_ is the equivalent to a space):

    1__The_sum_is:_6

    And inside your println parameters you have..

    input.charAt(length-length) + " " + Addition(length, input) + " " + "The sum is: " + Sum(sum, length, numericInput)

    Therefore..

    "1_" = input.charAt(length-length) + " "
    "_" = Addition(length, input)
    "The_sum_is:_6" = "The sum is: " + Sum(sum, length, numericInput)

    Try to locate the source of your error... and after all of this is done, (if you'd like) I can show you my approach to this program.
    Simplicity calls for Complexity. Think about it.

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