Question

In this exercise, write a complete Java program that reads integer numbers from the user until a negative value is entered. It should then output the average of the numbers, not including the negative number. If no non-negative values are entered, the program should issue an error message. You are required to use a do-while loop to solve this problem. Solutions that do not use a do-while loop will be given a zero. Make sure to add appropriate comments to your code. Two samples of how your program should run are shown below (user input is in bold):

Please enter some numbers (a negative to stop):

7

3

5

2

-1

Average: 4.25

Please enter some numbers (a negative to stop): -2

Error: no positive numbers provided

Answer 1

import java.util.*;
import java.util.Scanner;

public class Main
{
public static void main(String[] args) {
//scanner object creation
Scanner sc = new Scanner(System.in);
float sum=0,c=0,avg=0,temp=0;
  
System.out.println("Please Enter Some Numbers(a negative to stop): ");
//runs the loop
do
{
//reads input from user and store into temp variable
temp = sc.nextInt();
//checks the condition if entered number is negative ,if block will be executed
if(temp<0)
{
//prints the statement
System.out.println("Error: no positive numbers provided");
//breaks the while loop
break;
}
//entered number is not negatie then else block is executed
else
{
//calculates the sum of entered numbers   
sum+=temp;
// c variable keep count of how many numbers is entered by user, it is used in calculating average
c++;
}
}while(true);
//checks the condition sum is greater than 0 or not
if(sum>0)
{
//calculating the average entered numbers
avg = sum/c;
//statement prints the average
System.out.println("average: "+avg);
}
}
}

1 7 9 { { import java.util.*; 2 import java.util.Scanner; 3 4 public class Main 5-{ public static void main(String[] args) { //scanner object creation 8 Scanner sc = new Scanner(System.in); float sum=0,C=0, avg=0, temp=0; 10 11 System.out.println("Please Enter Some Numbers(a negative to stop): "); 12 //runs the loop 13 do 14 15 //reads input from user and store into temp variable 16 temp = sc.nextInt(); 17 //checks the condition if entered number is negative , if block will be executed 18 if(temp<0) 19 20 1/prints the statement 21 System.out.println("Error: no positive numbers provided"); 22 //breaks the while loop 23 break; 24 25 1/entered number is not negatie then else block is executed 26 else 27 { 28 // calculates the sum of entered numbers 29 sum+=temp; 30 // c variable keep count of how many numbers is entered by user, it is used in calculating average 31 C++; 32 33 }while(true); 34 // checks the condition sum is greater than o or not 35 if(sum>0) 36 37 //calculating the average entered numbers 38 avg = sum/c; 39 //statement prints the average 40 System.out.println("average: "+avg); 41 42 43 } } { }