SOURCE

function weightFn (list, count) {
    if (!list || !list.length || !count) return false;
    let sum = list.reduce((pre, cur) => pre+=cur, 0);
    if (sum % count === 0) return true;
    return false;
}

let list = [2,2,3,3,5];
// let list = [3,5,5,6,7];
let count = 3;

const result = weightFn(list, count);
console.log(result)