#include <iostream>
using namespace std;

class Stairs {
public:
    int stair;
    int up;
    int fin;

    void stepNeeded() {
        if (stair > 0) {
            if (up > 0) {
                    fin = (stair + up - 1) / up;
                    cout << fin <<endl;
            }else{
                cout << "불가능" <<endl;
            }
        }else{
            cout << "잘못된 입력" <<endl;
        }
    }
};

int main() {
    Stairs s;

    cin >> s.stair;
    cin >> s.up;
    s.stepNeeded();

}