match array index selected with other array and sum

match index and sum.js

const selected = [0, 2]
const products = [
  {
    price: 20000,
    ...
  },
  ...
]

totalPrice() {
  let total = 0
  // get index from itearation (ES6)
  for (const [productIndex, valueProduct] of products.entries()) {
    // filter
    selected.forEach((selectIndex) => {
      if (selectIndex === productIndex) {
        total += valueProduct.price
      }
    })
  }
  return total
}

totalPrice()