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Java - How to only count the inputted positive numbers

I am trying to find sum and averags of user inputed numbers and i also Need my program to only sum the positive numbers entered.
It needs to calculate only the positive numbers sum and ignore the negative inputs, would i put my num=0 or not?
import java.util.Scanner;
public class J12ForSumPos {
public static void main(String[] args) {
Scanner console = new Scanner(System.in);
int maxNumbers, i, num, average;
int sum = 0;
System.out.print("Enter Max Numbers: ");
maxNumbers = console.nextInt();
System.out.println();
for (i = 1; i <= maxNumbers; i = i + 1) {
System.out.print("Enter Value " + i + ": ");
num = console.nextInt();
sum = sum + num;
}
average = sum / maxNumbers;
if (sum >= 0) {
System.out.println();
System.out.println("Sum: " + sum);
System.out.println();
System.out.println("Average: " + average);
System.out.println();
} else {
System.out.println("Sum is: " + sum * 0);
System.out.println();
System.out.println("Cannot Calculate Average - no positives entered");
}
}
}

You can try something like this:
Scanner console = new Scanner(System.in);
int maxNumbers = 0;
int totalSum = 0; // Sum of all numbers (positive and negative)
int totalAverage = 0; // Average of all numbers (positive and negative)
int positiveSum = 0; // Sum of all positive numbers
int positiveAverage = 0; // Average of all positive numbers
int positiveNumberCount = 0; // Amount of positive numbers entered
System.out.print("Enter Max Numbers: ");
maxNumbers = console.nextInt();
System.out.println();
for(int i=1; i<=maxNumbers; i=i+1)
{
System.out.print("Enter Value " + i + ": ");
int num = console.nextInt();
if(num >= 0) {
positiveSum = positiveSum + num;
positiveNumberCount = positiveNumberCount + 1;
}
totalSum = totalSum + num;
}
positiveAverage = positiveSum / positiveNumberCount;
totalAverage = totalSum / maxNumbers;
It's up to you to decide whether or not to include 0 as a positive or a negative number, or exclude it. In my example it's being treated as a positive number.

Input numbers until 0, then calculate average

Okey, i need to make a program to calculate average. But, i need to input numbers, and when i want to stop i can input zero. Then, my program need to sum all entered numbers and calculate average of entered numbers. I made almost everyithing in my code but idk how to make a formula to calculate average, my program sum numbers and then divide by last entered number.
Scanner input = new Scanner(System.in);
System.out.println("Input numbers, 0 for stop!");
int number = input.nextInt();
int number1 = 1;
while (number != 0) {
number1 = (number + number1) / number; //here is my problem?
number = input.nextInt();
}
System.out.println("Average is: " + number1);

Your code is written great except you calculate the average wrong,
If you want to calculate the average on the fly you will need to know how much numbers you have read so far..
e.g:
Scanner input = new Scanner(System.in);
System.out.println("Input numbers, 0 for stop!");
int number = input.nextInt();
int average = number;
int counter = 1;
while (number != 0) {
average= (average * counter + number) / (counter + 1);
counter++;
number = input.nextInt();
}
System.out.println("Average is: " + average);
this code will give you the average after each step.
Another (simpler solution) is:
Scanner input = new Scanner(System.in);
System.out.println("Input numbers, 0 for stop!");
int number = input.nextInt();
double sum = 0;
int counter = 0;
while (number != 0) {
sum += number;
counter++;
number = input.nextInt();
}
System.out.println("Average is: " + sum/counter);

Average is the sum total of the numbers divided by the number of numbers, so you need to keep a running count of how many numbers you are inputting, as well as a running sum, and at the end, you divide the sum by the count. The sum should be a double just in case you end up with a fraction
Scanner input = new Scanner(System.in);
System.out.println("Input numbers, 0 for stop!");
double sum = 0;
int count = 0;
int number = input.nextInt();
while (number != 0) {
sum += number;
count++;
number = input.nextInt();
}
System.out.println("Average is: " + sum/count);

Read a list of nonnegative integers and to display the largest integer, the smallest integer and the average of all the integers

I have encountered some problems with the calculating of largest and smallest number... If the first number I entered is a larger number than the 2nd number input, it will not record the 1st number into the largest...
Take a look at the output, it will help elaborate better..
Calculation Error.. &
1st input problem..
Codes below!
public static void main(String[] args) {
int smallest = Integer.MAX_VALUE;
int largest = 0;
int number;
double totalAvg = 0;
double totalSum = 0;
int count = 0;
Scanner kb = new Scanner(System.in);
System.out.println("Enter few integers (Enter negative numbers to end input) :");
while (true) { //LOOP till user enter "-1"
number = kb.nextInt();
//Condition for the loop to break
if (number <= -1) {
System.out.println("End Of Input");
break;
} else {
count = count + 1;
}
if (number < smallest) { //Problem 1 : If 1st input num is bigger than 2nd input num,
smallest = number; // largest num will not be recorded..
} else {
largest = number;
}
totalSum = totalSum + number;
totalAvg = (totalSum / count);
}
System.out.println("The smallest number you have entered is : " + smallest);
System.out.println("The largest number you have entered is : " + largest);
System.out.println("The total sum is : " + totalSum);
System.out.println("The total average is : " + totalAvg);
System.out.println("Count : " + count);
} // PSVM

You could build an IntStream if you are using Java 8, and extract those numbers automatically using IntSummaryStatistics. You can find the official documentation from Oracle here.
Here is the code to achieve that:
List<Integer> input = new ArrayList<>();
while (true) { // LOOP till user enter "-1"
number = kb.nextInt();
// Condition for the loop to break
if (number <= -1) {
System.out.println("End Of Input");
break;
} else {
input.add(number);
}
}
IntSummaryStatistics z = input.stream() // gives Stream<Integer>
.mapToInt(Integer::intValue) // gives IntStream
.summaryStatistics(); // gives you the IntSummaryStatistics
System.out.println(z);
If you input 8 3 7 the output will be:
IntSummaryStatistics{count=3, sum=18, min=3, average=6.000000, max=8}
I hope it helps!

Do it like this:
public static void main(String[] args) {
int smallest = Integer.MAX_VALUE;
int largest = 0;
int number;
double totalAvg = 0;
double totalSum = 0;
int count = 0;
Scanner kb = new Scanner(System.in);
System.out.println("Enter few integers (Enter negative numbers to end input) :");
while (true) { //LOOP till user enter "-1"
number = kb.nextInt();
//Condition for the loop to break
if (number <= -1) {
System.out.println("End Of Input");
break;
} else {
count = count + 1;
}
if (number < smallest) { //Problem 1 : If 1st input num is bigger than 2nd input num,
smallest = number; // largest num will not be recorded..
}
//REMOVED ELSE ADDED another IF
if (number > largest){
largest = number;
}
totalSum = totalSum + number;
totalAvg = (totalSum / count);
}
System.out.println("The smallest number you have entered is : " + smallest);
System.out.println("The largest number you have entered is : " + largest);
System.out.println("The total sum is : " + totalSum);
System.out.println("The total average is : " + totalAvg);
System.out.println("Count : " + count);
} // PSVM

The problem is your if statement, as the logic is flawed. If the input number is smaller than smallest, then you update the smallest number. So far all is correct. The problem occurs, because you update largest in the else part. This means, if a number is not the smallest, largest is overwritten. But if the number is greater than the smallest, it is not automatically the largest. The right way to do this, is to check if the number is larger than the largest in a new if statement and update largest only in this case.

Java-Number of scores needs to be one less in answer

So here is my code:
package e7;
import java.util.Scanner;
public class Q1 {
public static void main(String[] args)
{
double[] scores = new double[10];
double sum = 0.0D;
int count = 0;
Scanner sc = new Scanner(System.in);
do {
System.out.print("Enter a new score (-1 to end): ");
scores[count] = sc.nextDouble();
if (scores[count] >= 0.0D)
sum += scores[count];
}
while (scores[(count++)] >= 0.0D);
System.out.println("The total number of scores is: " + count );
double average = sum / (count - 1);
int numOfAbove = 0;
int numOfBelow = 0;
for (int i = 0; i < count - 1; i++) {
if (scores[i] >= average)
numOfAbove++;
else
numOfBelow++;
}
System.out.printf("Average is " + "%.2f\n",average);
System.out.println("Number of scores above or equal to the average " + numOfAbove);
System.out.println("Number of scores below the average " + numOfBelow);
}
}
How do make it display the correct number of scores calculated? If I input 2 numbers and then do the -1 one to end it keeps saying 3 scores. Should only be two. How do I fix this? Thanks

System.out.println("The total number of scores is: " + count );
You probably want:
System.out.println("The total number of scores is: " + (count - 1));

You could also change your loop from a do while to a while loop as follows,
while (true) {
System.out.print("Enter a new score (-1 to end): ");
double tempDouble = sc.nextDouble();
if (tempDouble >= 0.0D)
scores[count] = tempDouble;
sum += scores[count];
count++;
else
break;
}
That way as if your double input isn't correct it would break out of the while loop when the user entered -1. You might have to tweak it a bit for your use case.

why is my count increasing when entering 0, it should exit the loop

I been working on this all night but couldn't make anything out it. I want my code to sum all the numbers the user enter, count how many times the user enters the number. then calculate the average.
and then find the max and min, easy right. well yeah if i was to be allowed to use arrays but this is for review and I hate while loops.
here's my code.
double integer = 1;
//double num = 0;
double sum = 0.0;
double average = 0.0;
Scanner input = new Scanner(System.in);
int count = 0;
// double char1=0;
double min = integer;
double max = integer;
// char letter = 'q';
while (integer != 0) {
System.out.println("Please enter an integer: ");
integer = input.nextInt();
sum += integer;
count++;
System.out.println("The sum of your numbers is: " + sum);
System.out.println("The number of values entered is: " + count);
System.out.println("");
if (integer > max)
max = integer;
else if (integer < min)
min = integer;
}
Here's the output:
Please enter an integer:
3
The sum of your numbers is: 3.0
The number of values entered is: 1
Please enter an integer:
2
The sum of your numbers is: 5.0
The number of values entered is: 2
Please enter an integer:
1
The sum of your numbers is: 6.0
The number of values entered is: 3
Please enter an integer:
0
The sum of your numbers is: 6.0
The number of values entered is: 4
The average of your sum is: 1.5
The max integer is: 3.0
The min integer is: 0.0
when the count increases by 1 my average comes out wrong. but why is 0 been counted as part of count and why my min always output 0 and not what the user enters. any and all help is much appreciated.
p.s. i have tried numerous ways but it doesnt work. if i try to change my count to start at -1 it solves my problem at hand with average but the count increases anyways so i know its incorrect. also the min problem stays there.
thanks guys

You need to add if condition to avoid increment when you enter 0.
You can use this code
// setting starting min and max value.
double min = Double.MAX_VALUE;
double max = Double.MIN_VALUE;
while (integer != 0) {
System.out.println("Please enter an integer: ");
integer = input.nextInt();
sum += integer;
if (integer != 0) { // added if condition
count++;
System.out.println("The sum of your numbers is: " + sum);
System.out.println("The number of values entered is: " + count);
System.out.println("");
if (integer > max)
max = integer;
if (integer < min) // changed 'else if' to 'if'
min = integer;
}
}
System.out.println("Max : " + max);
System.out.println("Min : " + min);

Try this:
For these cases it is best to use the conditional do while. And initialize min at the maximum value allowed.
double integer;
double sum = 0.0;
Scanner input = new Scanner(System.in);
int count = 0;
double min = Double.MAX_VALUE;
double max = 0;
do {
System.out.print("Please enter an integer: ");
integer = input.nextInt();
if (integer >0) {
sum += integer;
count++;
System.out.println("The sum of your numbers is: " + sum);
System.out.println("The number of values entered is: " + count);
System.out.println("");
if (integer > max)
max = integer;
if (integer < min)
min = integer;
}
} while (integer != 0);
System.out.println("avg: "+sum/count);
System.out.println("max: "+max);
System.out.println("min: "+min);

you will need to add an extra if condition to make it work.
I have made few changes as below in your code and it is working as expected.
double integer = 1;
//double num = 0;
double sum = 0.0;
double average = 0.0;
Scanner input = new Scanner(System.in);
int count = 0;
double min = integer;
double max = integer;
while (true) {
System.out.println("Please enter an integer: ");
integer = input.nextInt();
if(integer != 0)
{
sum += integer;
count++;
System.out.println("The sum of your numbers is: " + sum);
System.out.println("The number of values entered is: " + count);
System.out.println("");
if (integer > max)
max = integer;
else if (integer < min)
min = integer;
}
else
break;
}

double integer = 1;
double sum = 0.0;
double average = 0.0;
Scanner input = new Scanner(System.in);
int count = 0;
double min = Double.MAX_VALUE;
double max = Double.MIN_VALUE;
while (integer != 0) {
System.out.println("Please enter an integer(press zero to exit): ");
integer = input.nextInt();
if (integer > 0){
sum += integer;
count++;
if (integer > max)
max = integer;
if (integer < min)
min = integer;
}
}
System.out.println("The sum of your numbers is: " + sum);
System.out.println("Your count number is: " + count);
average = sum / count;
System.out.println("The average of your sum is: " + average);
System.out.println("The max integer is: " + max);
System.out.println("The min integer is: " + min);
}
}

You may try the below code
import java.util.Scanner;
public class ComputeDemo {
public static void main(String[] args) {
double integer = 1;
//double num = 0;
double sum = 0.0;
double average = 0.0;
Scanner input = new Scanner(System.in);
int count = 0;
// double char1=0;
double min = integer;
double max = integer;
// char letter = 'q';
while (integer != 0) {
System.out.println("Please enter an integer: ");
integer=input.nextInt();
if(integer>0)
{
sum += integer;
count++;
System.out.println("The sum of your numbers is: " + sum);
System.out.println("The number of values entered is: " + count);
System.out.println("");
if (integer > max)
max = integer;
else if (integer < min)
min = integer;
}
else
{
min=0;
System.out.println("The sum of your numbers is: " + sum);
System.out.println("The number of values entered is: " + count);
System.out.println("");
}
}
}
}