function calculateTotalCosts(salary, numWorkers, city) {
    var total = 5000+salary*numWorkers;
    switch(city) {
        case "NYC":
            total += 30000;
        break;
        case "BEJ":
            total += 25000;
        break;
        default:
            total += 10000;
    }
    return total;
}
console.log(alculateTotalCosts(40000, 3, "DLH"));