Sum of Found Indexes

Create a function which takes in an array of numbers and a number to find. Return the sum of every index in the array which matches the chosen number.

Examples

sumFoundIndexes([0, 3, 3, 0, 0, 3], 3) ➞ 8
// The number 3 was found at indexes 1, 2 and 5.
// 8 = 1 + 2 + 5

sumFoundIndexes([1, 2, 3, 4, 5, 6], 3) ➞ 2

sumFoundIndexes([100, 100, 100, 100, 100], 100) ➞ 10

sumFoundIndexes([5, 10, 15, 20], 2) ➞ 0

Notes

0 can be the result if no number in the array matches or if the only matching element is at index 0.