public class Pan {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int k = scanner.nextInt();

        int m = 2*n;
        if (m%k == 0){
            System.out.println(m/k);
        }
        else{

            System.out.println(m/k+1);
        }
    }
}
why Wrong Answer?