Question

14.8 Prog 8 Overload methods (find avg)

Write a program to find the average of a set numbers (assume that the numbers in the set is less than 20) using overload methods.

The program first prompts the user to enter a character; if the character is 'I' or 'i', then invokes the appropriate methods to process integer data set; if the character is 'R' or 'r', then invokes the appropriate methods to process real number data set; if the inputted character is not valid, print an error message.

The program MUST have the following six methods, in additional to the main method (6 points):

2 methods named inputValue that prompts the user to input N integers or N real numbers, the header of the method should be

    public static void inputValue (int[ ], int, Scanner)  
    public static void inputValue (double[ ], int, Scanner) 
                             Input to the method:    array of either int or double data type
                                                     an integer (numbers in the data set)
                                                     Scanner object
                              Output of the method:  None

2 method named findAvg that returns the average of the data, the header of the method should be

    public static double findAvg (int[ ], int) 
    public static double findAvg (double[ ], int)   
                           Input to the method:      array of either int or double data type
                                                     an integer (numbers in the data set)
                            Output of the method:    a real number (average)

2 method named printResult that prints the inputted data and average , the header of the method should be

    public static void printResult (int[ ], int, double) 
    public static void printResult (double[ ], int, double)   
                            Input to the method:      array of either int or double data type
                                                      an integer (numbers in the data set)
                                                      a real number (average)
                            Output of the method:     None

           Note: use System.out.format("is %.2f", avg); to format the average to 2 decimal place.

Find the average of integer data set by invoking appropriate methods in main method, format to 2 decimal places (2 points)

Enter a character: i
Enter a number: 4

Enter 4 integers: 2 4 6 10
The average of 2 4 6 10 is 5.50

Find the average of real number data set by invoking appropriate methods in main method, format to 2 decimal places (2 points)

Enter a character: R
Enter a number: 3

Enter 3 real numbers: 3.66   5.795  7.1203
The average of 3.66   5.795  7.1203 is 5.53

If the inputted character is not valid, print an error message (1 points)

Enter a character: t
t is not the valid character.

Answer 1

PROGRAM

/* import scanner class from util package */
import java.util.Scanner;

class average
{
/* input the integer values in array */
public static void inputValue (int in[], int n)
{
int i;
   Scanner sc=new Scanner(System.in);
   System.out.print("\n\nEnter " + n + " integers:");
   for(i=0;i<n;i++)
   {
   in[i]=sc.nextInt();
   }  
  
}
/* input the real values in array */
public static void inputValue (double rl[], int n)
   {
   int i;
   Scanner sc=new Scanner(System.in);
   System.out.print("\n\nEnter " + n + " real numbers:");
   for(i=0;i<n;i++)
   {
   rl[i]=sc.nextDouble();
   }  
   }
   /* calculate average of integers */
   public static double findAvg(int in[], int n)
   {
   int i;
   double a;
   int s=0;
   for(i=0;i<n;i++)
   {
   s=s+in[i];
   }
       /* convert the value to double */
       a=((double)s)/n;
       return a;
      
   }
   /* calculate average of real numbers */
public static double findAvg(double rl[], int n)
{  
   int i;
   double a;
   double s=0.0;
   for(i=0;i<n;i++)
   {
   s=s+rl[i];
   }
       a=(s/n);
       return a;
   }
   /* print average of integers */
   public static void printResult (int in[], int n, double avg )
{  
   int i;
   System.out.print("The average of ");
   for(i=0;i<n;i++)
   {
   System.out.print(in[i] + " ");
   }
/* print upto 2 decimal place */     
   System.out.format("is %.2f", avg);
   }
   /* print average of real values*/
public static void printResult (double rl[], int n, double avg)
{
   int i;
   System.out.print("The average of ");
   for(i=0;i<n;i++)
   {
   System.out.print(rl[i] + " " );
   }
/* print upto 2 decimal place */     
   System.out.format("is %.2f", avg);
  
}  
}

public class avg_cal
{
public static void main(String[] args)
{   
char ch;
       int n;
       double avg=0.0;
       /* integer array with not more than 20 values */
       int in[]=new int[20];
       /* double data type array with not more than 20 values */
       double rl[]=new double[20];
       /* sc object of scanner class */
       Scanner sc=new Scanner(System.in);
       /* ob object of average class */
average ob=new average();
       System.out.println();
       /* take character from console input */
System.out.print("Enter a character:");
ch=sc.next().charAt(0);
/* if i or I is pressed */      
if(ch=='i' || ch =='I')
{
System.out.print("Enter a number:");  
           n=sc.nextInt();
           /* call all functions with object ob */
           ob.inputValue(in,n);
           avg=ob.findAvg(in,n);
           ob.printResult(in,n,avg);
           System.out.println();
          
       }
       /* if r or R is pressed */  
else if(ch=='R' || ch =='r')
{
System.out.print("Enter a number:");  
           n=sc.nextInt();
           /* call all functions with object ob */
           ob.inputValue(rl,n);
           avg=ob.findAvg(rl,n);
           ob.printResult(rl,n,avg);
           System.out.println();
       }
       /* for wrong option press */
else
{
       System.out.println(ch + " is not the valid character.");
       }
}
}

SCREEN SHOT

OUTPUT