function solve(input) {
    let obj = {};

    for (let travelInfo of input) {
        let [country, town, cost] = travelInfo.split(" > ");

        if (!obj.hasOwnProperty(country)) {
            obj[country] = [];
        }
        let currentTown = obj[country].find((o) => o.town === town);
        if (!currentTown) {
            obj[country].push({town, cost: (+cost)})
        } else if ((+cost) < currentTown.cost) {
            currentTown.cost = (+cost);
        }
    }

    let output = "";
    Object.keys(obj).sort((a,b) => a.toLowerCase().localeCompare(b.toLowerCase())).forEach((country) => {
        output += `${country} -> `;
        obj[country].sort((a, b) => a.cost - b.cost).forEach((town) => {
            output += `${town.town} -> ${town.cost} `
        });
        output += '\n'
    });

    console.log(output)
}