method in class cannot be applied to given types

26
votes

I'm creating a program that generates 100 random integers between 0 and 9 and displays the count for each number. I'm using an array of ten integers, counts, to store the number of 0s, 1s, ..., 9s.)

When I compile the program I get the error:

RandomNumbers.java:9: error: method generateNumbers in class RandomNumbers cannot be applied to given types;
generateNumbers();

required: int[]

found:generateNumbers();

reason: actual and formal argument lists differ in length

I get this error for the lines of code that I call the methods generateNumbers() and displayCounts() in the main method.

    public class RandomNumbers {

       public static void main(String[] args) {

            //declares array for random numbers
        int[] numbers = new int [99];

        //calls the generateNumbers method
        generateNumbers();

        //calls the displayCounts method        
        displayCounts();
    }

    //***************************************************************** 

    private static int generateNumbers(int[] numbers){

        for(int i = 0; i < 100; i++){
            int randomNumber;
            randomNumber = (int)(Math.random() *10);
            numbers[i] = randomNumber;
        return randomNumber;
        }

    }

    //***************************************************************** 

    private static void displayCounts(int[] numbers){
        int[] frequency = new int[10];

        for(int i = 0, size = numbers.length; i < size; i++ ){
            System.out.println((i) + " counts = " + frequency[i]);
        }

    }//end of displayCounts

    }//end of class
5
javaarraysmethodsarguments
As a side note, generateNumbers returns the value each time when i is 0, so it will always jump out of the loop and never fill the array. – Evan Trimboli
Another side note: I guess you should also declare your numbers array of size 100, not 99. (int[] numbers = new int [100];) Otherwise you will only print 99 numbers. – Florian Minges

5 Answers

23
votes

generateNumbers() expects a parameter and you aren't passing one in!

generateNumbers() also returns after it has set the first random number - seems to be some confusion about what it is trying to do.

3
votes

call generateNumbers(numbers);, your generateNumbers(); expects int[] as an argument ans you were passing none, thus the error

0
votes

The generateNumbers(int[] numbers) function definition has arguments (int[] numbers)that expects an array of integers. However, in the main, generateNumbers(); doesn't have any arguments.

To resolve it, simply add an array of numbers to the arguments while calling thegenerateNumbers() function in the main.

0
votes

I think you want something like this. The formatting is off, but it should give the essential information you want.

   import java.util.Scanner;
public class BookstoreCredit 
{

   public static void computeDiscount(String name, double gpa) 
   {
      double credits;
      credits = gpa * 10;
      System.out.println(name + " your GPA is " +
         gpa + " so your credit is $" + credits);
   
   }

   public static void main (String args[]) 
   {
      String studentName;
      double gradeAverage;
      Scanner inputDevice = new Scanner(System.in);
      System.out.println("Enter Student name: ");
      studentName = inputDevice.nextLine();
      System.out.println("Enter student GPA: ");
      gradeAverage = inputDevice.nextDouble();  
      
      computeDiscount(studentName, gradeAverage);
   }
}
0
votes

pass the array as a parameter when call the function, like

(generateNumbers(parameter),displayCounts(parameter))