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Thread: Create 100 integers?

  1. #1
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    Default Create 100 integers?

    Hi all.

    This program is meant to do the following:

    1: create a new txt file
    2: write 100 random integers to it
    3: read it back into an array
    4: sort the array
    5: print contents of array

    I have everything working apart from part 2. I can't get it to create 100 numbers. Sometimes it does 50, other times 62, 25, 99 etc.
    Not sure on how to fix this. Any help much appreciated.

    My code below.

     
    import java.io.*;
    import java.util.*;
     
    public class Q3
    {
    	public static void main(String[] args)
    	//Throw any exceptions
    	throws Exception
    	{
    		// Create file called Q3.txt
    		FileWriter newFileWriter = new FileWriter("Q3.txt");
    		BufferedWriter newFileOut = new BufferedWriter(newFileWriter);
     
    		//Random Number Generator
    		Random numberGenerator = new Random();
     
    		//Write 100 random numbers to Q3.txt
    		for (int i = 0; i < 100; i++)
    		{
    			//while number of numbers is less than 100, increment the counter
    			//and enter a random number to the file followed by a space
    			int randomNumber = numberGenerator.nextInt(100);
    			newFileOut.write(randomNumber + " ");
    		}
    		//Close the file writer
    		newFileOut.close();
     
    		//crate file scanner to read file
    		Scanner input = new Scanner(new File("Q3.txt"));
    		//create array with contents of the file
    		int[] array = new int[input.nextInt()];
    		//every next number is sent to next position on the array
    		for (int i = 0; i < array.length; i++)
    		    array[i] = input.nextInt();
    		//sort the array in ascending order
    		Arrays.sort(array);
    		//parse the array contents to a string and print the string
    		System.out.println(Arrays.toString(array));
    		//close the file reader
    		input.close();
    	}
    }


  2. #2
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    Default Re: Create 100 integers?

    How are you determining that the correct number of integers is NOT being written to the file? Try inspecting the file, paying particular attention to the first number in the file.

    Then, consider the reason you're seeing variable results is because of this line:

    int[] array = new int[input.nextInt()];

    Put the two findings together to determine the root cause and design a fix.

  3. #3
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    Default Re: Create 100 integers?

    That helped, solved and working.

    Thank you sir.

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