Associative Arrays 06. Travel Time

function travelTime(input) {
    let countries = {};

    input.forEach(line => {
        let [country, town, price] = line.split(' > ');
        price = Number(price);
        if (!countries.hasOwnProperty(country)) {
            countries[country] = {};
            countries[country][town] = price;
        } else {
            let existingCountryObj = countries[country];
            if (!existingCountryObj.hasOwnProperty(town)) {
                countries[country][town] = price;
            } else {
                let oldPrice = countries[country][town];
                price = Math.min(oldPrice, price);
                countries[country][town] = price;
            }
        }
    });
    let sorted = Object.entries(countries).sort((firstPair, secondPair) => {
        let [firstCountry, firstData] = firstPair;
        let [secondCountry, secondData] = secondPair;
        return firstCountry.localeCompare(secondCountry);
    });
    for (let [name, towns] of sorted) {
        let sortedTowns = Object.entries(towns).sort((firstTown, secondTown) => {
            let firstPrice = firstTown[1];
            let secondPrice = secondTown[1];
            return firstPrice - secondPrice;
        });
        let output = `${name} -> `;
        for (let townName in towns) {
            let townPrice = towns[townName];
            output += `${townName} -> ${townPrice} `;
        }
        console.log(output);
    }
}