Write a Java program to calculate the sum of all elements in an array.

public class SumOfArray {
    public static void main(String[] args) {
        int array[] = { 10, 20, 30, 40, 50, 10 };
        int sum = 0;

        // Advanced for loop (enhanced for / for-each)
        for (int num : array) {
            sum = sum + num;   // or: sum += num
        }

        System.out.println("Sum of array elements is: " + sum);
    }
}

Sum of array elements is: 160

int[] array = { 10, 20, 30, 40, 50 };
int sum = 0;

for (int i = 0; i < array.length; i++) {
    sum += array[i];
}
System.out.println("Sum: " + sum);  // 150

import java.util.stream.IntStream;

int[] array = { 10, 20, 30, 40, 50 };

int sum = IntStream.of(array).sum();
System.out.println("Sum: " + sum);  // 150

// Or using Arrays.stream()
int sum2 = java.util.Arrays.stream(array).sum();

int[] array = { 10, 20, 30, 40, 50 };

int sum = 0, max = array[0], min = array[0];

for (int num : array) {
    sum += num;
    if (num > max) max = num;
    if (num < min) min = num;
}

System.out.println("Sum:     " + sum);                          // 150
System.out.println("Count:   " + array.length);                 // 5
System.out.printf("Average: %.2f%n", (double)sum/array.length); // 30.00
System.out.println("Max:     " + max);                          // 50
System.out.println("Min:     " + min);                          // 10

int[] array = { Integer.MAX_VALUE, 1, 2, 3 };

// Bug: int overflow!
int badSum = 0;
for (int n : array) badSum += n;
System.out.println(badSum);  // negative! overflow

// Fix: use long
long goodSum = 0L;
for (int n : array) goodSum += n;
System.out.println(goodSum);  // correct: 2147483653

// Sum all product quantities in a cart
List<WebElement> qtyFields = driver.findElements(By.css(".cart-qty"));
int totalItems = 0;
for (WebElement qty : qtyFields) {
    totalItems += Integer.parseInt(qty.getAttribute("value"));
}
assertEquals(totalItems, 5, "Cart should have 5 items total");