[java] How to perform a sum of an int[] array

Given an array A of 10 ints, initialize a local variable called sum and use a loop to find the sum of all numbers in the array A.

This was my answer that I submitted:

sum = 0;
while( A, < 10) {
   sum = sum += A;
}

I didn't get any points on this question. What did I do wrong?

int sum=0;
for(int i:A)
  sum+=i;

Here is an efficient way to solve this question using For loops in Java

 public static void main(String[] args) {

    int [] numbers = { 1, 2, 3, 4 };
    int size = numbers.length;

    int sum = 0;
    for (int i = 0; i < size; i++) {
        sum += numbers[i];
    }

    System.out.println(sum);
}

When you declare a variable, you need to declare its type - in this case: int. Also you've put a random comma in the while loop. It probably worth looking up the syntax for Java and consider using a IDE that picks up on these kind of mistakes. You probably want something like this:

int [] numbers = { 1, 2, 3, 4, 5 ,6, 7, 8, 9 , 10 };
int sum = 0;
for(int i = 0; i < numbers.length; i++){
    sum += numbers[i];
}
System.out.println("The sum is: " + sum);

int sum = 0;
for(int i = 0; i < A.length; i++){
  sum += A[i];
}

Once java-8 is out (March 2014) you'll be able to use streams:

int sum = IntStream.of(a).sum();

or even

int sum = IntStream.of(a).parallel().sum();