Arrange Javascript Arrays

Question

I have array of cars and an array of price corresponding to each car.

I want to implement the function highest3 which will return an array of 3 cars in order by their p

Answer 1

Here is a solution for you. First of all it creates an array of objects which represent the cars and their associated values (joinCarPrices).

Then we perform a sort, using the custom sorting function priceSort by using the Array#sort function. Which sorts the cars based on the algorithm you asked for. Lastly, we use Array#slice to only have the 3 highest prices cars.

var cars = ["Ferrari", "Lamborghini", "Jaguar", "Hummer", "Toyota"],
price = [12, 34.5, 3.54, 45.9, 3.44],
result,
joinCarPrices = function () {
    var index = 0,
        carPrices = [];

    for (index = 0; index < cars.length; index++) {
        carPrices[index] = {
            'car': cars[index],
            'price': price[index]
        };
    }

    return carPrices;
},
priceSort = function (a, b) {
    // If the first car is less than the second car
    if (a.price < b.price) {
        return 1;
    } else if (a.price > b.price) {
        // If the first car is more than the second car
        return -1
    } else {
        // Else sort by the car name
        return a.car < b.car ? -1 : 1;
    }
};

cars = joinCarPrices(); // Join the Cars/Prices together as Objects, into an array
result = cars.sort(priceSort); // Sort the Cars based on the Price Sort function
result = result.slice(0, 3); // Slice to only give us array items 0-3
console.log(result);

And heres a JSFiddle showing it working!

Answer 2

This is only one possible solution:

//I assume you get the arrays correctly linked i.e price[0] is the 
//price of cars[0]
var cars = ["Ferrari", "Lamborghini", "Jaguar", "Hummer", "Toyota"];
var price = [12, 34.5, 3.54, 45.9, 3.44];

result == ["Hummer", "Lamborghini", "Ferrari"];

function highest3 (cars, price) {

//First we unite the two arrays 
carsAndPrice = [];
for (var i = 0; i < cars.length; i = i +1)
    carsAndPrice[i] = {car:cars[i],price:price[i]};
}
//Now that the price and the cars are strongly linked we sort the new array
//I'm using bubble sort to sort them descending this seems to be more of 
//a beginner question
var swapped;
    do {
        swapped = false;
        for (var j=0; j < carsAndPrice.length-1; i++) {
            if (carsAndPrice[i].price < carsAndPrice[i+1].price) {
                var temp = carsAndPrice[i];
                carsAndPrice[i] = a[i+1];
                carsAndPrice[i+1] = temp;
                swapped = true;
            }
        }
    } while (swapped);
  //return the name of the first 3 cars from the array
  var result = [];
  result[0] = carsAndPrice[0].price; //Most expensive
  result[1] = carsAndPrice[1].price;
  result[2] = carsAndPrice[2].price;
  }