#include <cstdlib>
#include <iostream>
#include <sstream>
#include <string>


using namespace std;

float secti(float a ,float b) {
    return a + b;
}
float odecti(float a ,float b) {
    return a - b;
}
float nasob(float a ,float b) {
    return a * b;
}
float del(float a ,float b) {
    return a / b;
}

// 1
float (*prvni)  (float, float);

// 2
float (*calc[])(float,float) = { secti, odecti, nasob, del };

void handler(void) {
    float cislo;
    float prvni = 5.4f;
    float druhe = 8.0f;
    string in;
    int op = 0;
    string operace[] = { "scitani", "odecitani", "nasobeni", "deleni" };

    cout << "Zadej cisla, pro skonceni stiskni X" << endl;
    /*while (true) {
        if (cin >> cislo) {
            druhe = prvni;
            prvni = cislo;
        } else if (cin >> in) {
            if (in == "X" || in == "x") {
                break;
            }
        }
    }*/

    cout << "Pomoci klaves A a S vyber operaci, klavesa P provede operaci." << endl;
    while (true) {
        cout << operace[op] << endl;
        cin >> in;

        if (in == "P" || in == "p" ) {
            cout << (*calc[op])(prvni,druhe) << endl;

            return;
        }

        if (in == "S" || in == "s" ) {
            op = (++op % 4);
        }
        if (in == "A" || in == "a") {
            if (op == 0) {
                op = 3;
            } else {
                --op;
            }
        }
    }

}


int main(int argc, char** argv) {

    handler();

    // 3


    return 0;
}