Реализация Алгоритма калькулятора

 #include  

 

using namespace std; 

 

#define ERR 1e10 

#define EPS 1e-6 

 

class Calculator{ 

private: 

    double x, y, res; 

    char op; 

public: 

    double getRes(){ 

        return res; 

    } 

    Calculator(int a, int b, char o){ 

        x = a; 

        y = b; 

        op = o; 

    } 

    void solve(){ 

        switch(op){ 

            case '+': 

                res = x + y; 

                break; 

            case '-': 

                res = x - y; 

                break; 

            case '*': 

                res = x * y; 

                break; 

            case '/': 

                res = x / y; 

                break; 

            default: 

                res = ERR; 

                break; 

        } 

    } 

}; 

 

int main(){ 

    int first, second; 

    char oper; 

    cout > first; 

    cout > second; 

    cout > oper; 

    Calculator calc = Calculator(first, second, oper); 

    calc.solve(); 

    cout

 #include  

#include  

 

#define get_by_user(s, fmt, var) \ 

    printf("%s = ", s);          \ 

    scanf(fmt, &var); 

 

static int calculate(int first, int second, 

                     char op) 

{ 

    switch (op) 

    { 

        case '+': return first + second; 

        case '-': return first - second; 

        case '*': return first * second; 

        case '/': return first / second; 

    } 

     

    fprintf(stderr, "Failed to calculate\n"); 

     

    exit(EXIT_FAILURE); 

} 

 

int main(void) 

{ 

    char op; 

    int first, second, result; 

     

    get_by_user("first", "%d", first); 

    get_by_user("second", "%d", second); 

    get_by_user("op", "%*c%c", op); 

     

    result = calculate(first, second, op); 

     

    printf("\n%d %c %d = %d\n", first, op, 

                              second, result); 

     

    return EXIT_SUCCESS; 

}