function solve(city, amount) {
    amount = Number(amount);
    let komisionna = Number

    if (amount < 0) {
        console.log(`error`);
        return;
    }

    if (amount >= 0 && amount <= 500) {
        switch(city){
            case `Sofia`:
             komisionna = amount * 0.05;
             break;

             case `Varna`:
             komisionna = amount * 0.045;
             break;;

             case `Plovdiv`:
             komisionna = amount * 0.055;
             break;


        }


    }

         if (amount > 500 && amount <= 1000) {
        switch(city){
            case `Sofia`:
             komisionna = amount * 0.07;
             break;

             case `Varna`:
             komisionna = amount * 0.075;
             break;;

             case `Plovdiv`:
             komisionna = amount * 0.08;
             break;


        }


    }

        if (amount > 1000 && amount <= 10000) {
        switch(city){
            case `Sofia`:
             komisionna = amount * 0.08;
             break;

             case `Varna`:
             komisionna = amount * 0.1;
             break;;

             case `Plovdiv`:
             komisionna = amount * 0.12;
             break;


        }


    }


      if (amount > 10000) {
        switch(city){
            case `Sofia`:
             komisionna = amount * 0.12;
             break;

             case `Varna`:
             komisionna = amount * 0.13;
             break;;

             case `Plovdiv`:
             komisionna = amount * 0.145;
             break;


        }


    } console.log(komisionna.toFixed(2));




}