Sum of all numbers in an array

Given an array arr of valid finite numbers, return the sum of all elements.

Examples

Input: arr = [1, 2, 3]
Output: 6

Input: arr = [5]
Output: 5

Input: arr = []
Output: 0

Input: arr = [-1, 5, -4]
Output: 0

Constraints

• Input is always a valid array.
• All elements are guaranteed to be finite numbers.
• No need to validate for invalid inputs.

Function Signature

function sumArray(arr) {
  // Your code here
}

Test Cases

• Empty: []
• Single element: [5], [0]
• Small: [1, 2], [1, 2, 3]
• Mixed values: [-1, 2, -3, 4], [10, -5, 5, -10]
• Large sets: [1..10], [10, 20, 30, 40, 50]
• With decimals: [1.5, 2.5, 3], [-1.2, 2.2]