JSFiddle - React, Tailwind, and code Playground

JavaScript

function sum(...values) {
    let sum = 0;
    for (let i = 0; i < values.length; i++) {
        sum += values[i];
    }
  
    return sum;
}
console.log(sum(1));
console.log(sum(1, 2));
console.log(sum(1, 2, 3));
console.log(sum(1, 2, 3, 4));