JavaScript: Compute the sum of an array of integers

JavaScript Function: Exercise-4 with Solution

Sum of Array Elements

Write a JavaScript program to compute the sum of an array of integers.

Example : var array = [1, 2, 3, 4, 5, 6]
Expected Output : 21

Visual Presentation:

Sample Solution-1:

JavaScript Code:

// Function to calculate the sum of elements in an array using recursion.
var array_sum = function(my_array) {
 // Base case: if the array has only one element, return that element.
 if (my_array.length === 1) {
 return my_array[0];
 }
 else {
 // Recursive case: pop the last element and add it to the sum of the remaining elements.
 return my_array.pop() + array_sum(my_array);
 }
};
// Example usage: Calculate and print the sum of elements in the array [1, 2, 3, 4, 5, 6].
console.log(array_sum([1, 2, 3, 4, 5, 6])); 

Output:

21

Flowchart:

Flowchart: JavaScript recursion function- Compute the sum of an array of integers

Live Demo:

See the Pen javascript-recursion-function-exercise-4 by w3resource (@w3resource) on CodePen.

Sample Solution-2:

JavaScript Code:

// Function to calculate the sum of elements in an array using recursion.
function arraySumRecursive(arr, index = 0) {
 // Base case: if the index exceeds the array length, return 0.
 if (index>= arr.length) {
 return 0;
 } else {
 // Recursive case: add the current element to the sum of the rest of the array.
 return arr[index] + arraySumRecursive(arr, index + 1);
 }
}
// Example usage: Calculate and print the sum of elements in the array [1, 2, 3, 4, 5, 6].
console.log(arraySumRecursive([1, 2, 3, 4, 5, 6])); 

Output:

21

Flowchart:

Flowchart: JavaScript recursion function- Compute the sum of an array of integers

For more Practice: Solve these Related Problems:

• Write a JavaScript function that recursively computes the sum of an array of integers without using loops.
• Write a JavaScript function that sums all the elements in an array and returns zero for an empty array.
• Write a JavaScript function that recursively computes the sum of an array while skipping non-numeric values.
• Write a JavaScript function that uses a divide and conquer approach recursively to compute the sum of array elements.

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