import java.util.Scanner;

public class Main {
    public static void main(String[] args) {

        Scanner input = new Scanner(System.in);
        double numberOf = input.nextDouble();
        double numberAtATime = input.nextDouble();
        double timeToMake = input.nextDouble();
        double result;


        result = timeToMake * Math.ceil(numberOf / numberAtATime);
        System.out.println((int)result);

    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {

        Scanner input = new Scanner(System.in);
        double numberOf = input.nextDouble();
        double numberAtATime = input.nextDouble();
        double timeToMake = input.nextDouble();
        double result;


        result = timeToMake * Math.ceil(numberOf / numberAtATime);
        System.out.println((int)result);

    }
} Main public static void main(String[] args) {

        Scanner input = new Scanner(System.in);
        double numberOf = input.nextDouble();
        double numberAtATime = input.nextDouble();
        double timeToMake = input.nextDouble();
        double result;


        result = timeToMake * Math.ceil(numberOf / numberAtATime);
        System.out.println((int)result);

    } main {

        Scanner input = new Scanner(System.in);
        double numberOf = input.nextDouble();
        double numberAtATime = input.nextDouble();
        double timeToMake = input.nextDouble();
        double result;


        result = timeToMake * Math.ceil(numberOf / numberAtATime);
        System.out.println((int)result);

    } Scanner input = new Scanner(System.in); input new Scanner(System.in) double numberOf = input.nextDouble(); numberOf input.nextDouble() input.nextDouble input double numberAtATime = input.nextDouble(); numberAtATime input.nextDouble() input.nextDouble input double timeToMake = input.nextDouble(); timeToMake input.nextDouble() input.nextDouble input double result; result result = timeToMake * Math.ceil(numberOf / numberAtATime) result timeToMake * Math.ceil(numberOf / numberAtATime) timeToMake Math.ceil(numberOf / numberAtATime) Math.ceil Math numberOf / numberAtATime numberOf numberAtATime System.out.println((int)result) System.out.println System.out System System.out (int)result String[] args args public class Main {
    public static void main(String[] args) {

        Scanner input = new Scanner(System.in);
        double numberOf = input.nextDouble();
        double numberAtATime = input.nextDouble();
        double timeToMake = input.nextDouble();
        double result;


        result = timeToMake * Math.ceil(numberOf / numberAtATime);
        System.out.println((int)result);

    }
} public class Main {
    public static void main(String[] args) {

        Scanner input = new Scanner(System.in);
        double numberOf = input.nextDouble();
        double numberAtATime = input.nextDouble();
        double timeToMake = input.nextDouble();
        double result;


        result = timeToMake * Math.ceil(numberOf / numberAtATime);
        System.out.println((int)result);

    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {

        Scanner input = new Scanner(System.in);
        double numberOf = input.nextDouble();
        double numberAtATime = input.nextDouble();
        double timeToMake = input.nextDouble();
        double result;


        result = timeToMake * Math.ceil(numberOf / numberAtATime);
        System.out.println((int)result);

    }
}
