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whar is wrong with this code??

Use the keyboard to enter numbers, and then calculate the arithmetic mean.
If the user enters -1, display the arithmetic mean of all entered numbers and end the program.
-1 should not be included in the calculation.

Here are some examples:
a) if you enter the numbers
1
2
2
4
5
-1
then we display
2.8

b) if you enter the numbers
4
3
2
1
-1
then we display
2.5

Hint: one of the solutions to this problem uses the following construct:

while (true) {
    int number = read the number;
    if (check whether the number is -1)
        break;
}

Requirements:

The program must read data from the keyboard.
The program should display data on the screen.
After entering -1, the program must correctly terminate.
If you sequentially enter the numbers 1, 2, 2, 4, 5 and -1, the program should display 2.8.
If you sequentially enter the numbers -100, 0, 100, and -1, the program should display 0.0.
If you sequentially enter the numbers 1 and -1, the program should display 1.0.
The displayed result should match the task conditions for any input data.

package com.codegym.task.task05.task0507; /* Arithmetic mean */ import java.io.BufferedReader; import java.io.InputStreamReader; public class Solution { public static void main(String[] args) throws Exception { int n = 0; int count = 0; double result; for (int i = 1; ; i++) { count++; BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); int a = Integer.parseInt(reader.readLine()); if (a != -1){ count++; } else if (a == -1){ result =(double)n/count; System.out.println(result); break; } } } }

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Fido Lost

Level 8 , Timmins, Canada

17 May 2019, 21:01

solution

You are incrementing count twice: on line 18 and then again on line 23.

Abdur Rehman

Level 7 , Faisalabad, Pakistan

18 May 2019, 06:43

after removing the counter on 18 i had to write n = n+ a on line 24 to solve it

ion

Level 8 , Athens, Greece

17 May 2019, 17:31

Maybe you didn't understand the conditions very well.. You have to add all the numbers together positive and negative ones, then divide them by their plenty.. For example -> (1+2+3+4+5) / 5 => 15 / 5 = 3. There is no need of counting positive and negative numbers. Also, make sure that your variable will be 'double'. (15 / 5 = 3.0) ;)

Khairul

Level 11

17 May 2019, 11:43

useful

In your code, you are just reading the new numbers from the keyboard. But to perform the mean of some numbers, you also need to add all those numbers and divide the sum by the numbers added, right? But you are not summing the newly entered numbers from the keyboard. So, just add a new variable in which you will add the new entered number from the keyboard with the previous value of the summation. For example, Let me input, 1 2 3 4 5 -1 After reading each number, I have to add the new number with the total sum and also increase the variable count by 1. The sum will be, sum = 15 (excluding -1, as it is the indication to stop) and variable count = 5 (excluding -1 as it is the indication to stop) Hope that helps you to find out the bug in your code. If you have further questions, feel free to ask.

Abdur Rehman

Level 7 , Faisalabad, Pakistan

18 May 2019, 06:33

int n = 0; int count = 0; double result; for (int i = 1; ; i++) { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); int a = Integer.parseInt(reader.readLine()); if (a != -1){ count++; n = n+ a; } else if (a == -1){ result =(double)n/count; System.out.println(result); break; } }

Abdur Rehman

Level 7 , Faisalabad, Pakistan

18 May 2019, 06:33

is this what you are asking?

Abdur Rehman

Level 7 , Faisalabad, Pakistan

18 May 2019, 06:40

i got it actually i had n = n+a in my code before but it didnt work cuz of two counters so now it is solved

Khairul

Level 11

18 May 2019, 19:02

Hmm, good