dop lab for Bezus №1

// Лабораторная работа для Гайделя №1 (допзадание. Рассчет веса на других планетах)
#include <iostream>

using namespace std;

// Продолжение работы программы
bool Prod()
{
    cout << "Continue Y/N" << endl;
    char yn;
    cin >> yn;
    cin.clear();
    if (yn == 'Y' && cin.get() == '\n') return true;
    else if (yn == 'N' && cin.get() == '\n') return false;
    else
    {
        while (cin.get() != '\n');
        cout << "Error. Try again" << endl;
        Prod();
    }
}

// Ввод первой планеты
char inputFirstPlanet()
{
    cout << "Earth(E)" << endl << "Venus(V)" << endl << "Mars(M)" << endl;
    char firstPlanet;
    cin >> firstPlanet;
    cin.clear();
    if (firstPlanet == 'E' || firstPlanet == 'V' || firstPlanet == 'M') return firstPlanet;
    else
    {
        while (cin.get() != '\n');
        cout << "Error. Try again" << endl;
        return inputFirstPlanet();
    }
}

// Ввод второй планеты
char inputSecondPlanet()
{

    cout << "Earth(E)" << endl << "Venus(V)" << endl << "Mars(M)" << endl;
    char secondPlanet;
    cin >> secondPlanet;
    cin.clear();
    if (secondPlanet == 'E' || secondPlanet == 'V' || secondPlanet == 'M') return secondPlanet;
    else
    {
        while (cin.get() != '\n');
        cout << "Error. Try again" << endl;
        return inputSecondPlanet();
    }
}

// Получение отношения масс планет
double getCoefficient(char firstPlanet, char secondPlanet)
{
    if (firstPlanet == 'E' && secondPlanet == 'V') return 0.82;
    if (firstPlanet == 'E' && secondPlanet == 'M') return 1.1;
    if (firstPlanet == 'V' && secondPlanet == 'E') return 1.22;
    if (firstPlanet == 'V' && secondPlanet == 'M') return 1.34;
    if (firstPlanet == 'M' && secondPlanet == 'E') return 0.9;
    if (firstPlanet == 'M' && secondPlanet == 'V') return 0.75;
    if (firstPlanet == secondPlanet) {
        cout << "Error. First planet = second planet" << endl;
        return Prod();
    }
}

// Получение веса на второй планете
double getSecondWeight(double coefficient, double firstWeight) {
    return coefficient * firstWeight;
}


// Получение веса на первой планете
double inputFirstWeight() {
    double firstWeight;
    cin >> firstWeight;
    cin.clear();
    if (firstWeight > 0 && cin.get() == '\n') return firstWeight;
    else {
        while (cin.get() != '\n');
        cout << "Error. Try again" << endl;
        inputFirstWeight();
    }
}

int main()
{
    char firstPlanet;
    char secondPlanet;
    double coefficient;
    double firstWeight;
    double secondWeight;

    do {

        cout << "select a first planet" << endl;
        firstPlanet = inputFirstPlanet();

        cout << "first weight = ";
        firstWeight = inputFirstWeight();

        cout << "select a second planet" << endl;
        secondPlanet = inputSecondPlanet();

        coefficient = getCoefficient(firstPlanet, secondPlanet);

        secondWeight = getSecondWeight(coefficient, firstWeight);

        cout << "second weight = " << secondWeight << endl;

    } while (Prod());
    system("pause");
    return 0;
}