odin-default-js-exercises/sumAll/sumAll.js

16 lines
389 B
JavaScript

const sumAll = function (numStart, numEnd) {
// final sum variable
let sum = 0;
if (numStart < 0 || numEnd < 0 || typeof numStart != "number" || typeof numEnd != "number") {
return "ERROR";
} else if (numStart > numEnd) {
[numStart, numEnd] = [numEnd, numStart];
}
for (let i = numStart; i <= numEnd; i++) {
sum += i;
}
return sum;
};
module.exports = sumAll;