const findSum = n => { let countArr = [] for(let i = 0; i <= n; i++) if(i % 3 === 0 || i % 5 === 0) countArr.push(i) return countArr.reduce((acc , curr) => acc + curr) } console.log(findSum(5))
const findSum = n => { let countArr = [] for(let i = 0; i <= n; i++) countArr.push(i) let finalArr = countArr.map(digit => { if(digit % 3 === 0 || digit % 5 === 0) return digit else return 0 }).reduce((acc , curr) => acc + curr) return finalArr } console.log(findSum(10))