Visual Studio Community - Tutorial

I started playing around with the free full featured version of MS Visual Studio Visual Studio Community.
I found the tutorial useful to get started but not very robust. I/O (cin) can be little tricky to deal with
so I'm releasing this for the c++ newbies to help them ramp up quicker.

CalcTutorial.cpp

  //////////////////////////////////////////////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////
//// 
//// Author: Adam Danischewski, Created Date: 20190812, Version: v1.0
//// Derivative Work - Released under Creative Commons License CC BY-SA 4.0
//// Orig. Source: https://tutorials.visualstudio.com/cpp-calculator/intro
////
 ///////////////////////////////////////////////////////////////////////////
  //////////////////////////////////////////////////////////////////////////

#include <iostream>
#include "Calc.h"
#include <string>

using namespace std;

int main()
{
 double x = 0.0;
 double y = 0.0;
 double result = 0.0;
 const int BUFCLR = 10000; //Note: it will loop until the buffer "makes sense".   
 string myinput;
 char oper = '+';

 cout << "Calculator Console Application - (Type \"exit\" to quit)" << endl << endl;
 cout << "Please enter the operation to perform. Format: a+b | a-b | a*b | a/b"
  << endl;

 Calculator c;
 while (true)
 { 
  if (cin.fail()) {
   cin.clear();
   cin.ignore(BUFCLR, '\n');
  }
  cout << "Calc: ";
  if (cin >> x >> oper >> y) { 
   switch (oper) {
   case '/':
   case '+':
   case '-':
   case '*':
    break;
   default:
    cout << "Error: Invalid operator (" << oper << "), operator must be in [+-*/]." << endl;
    continue;
   }
  if (oper == '/' && y == 0) {
   cout << "Error: Division by 0 exception, RHS must be > 0." << endl;
   continue;
  }
  result = c.Calculate(x, oper, y);
  cout << "Result is: " << result << endl;
  }
  else { 
   cin.clear(); // Clear cin fail state. 
   getline(cin, myinput);
   if (myinput == "exit") {
    cout << "Thanks for using Calc, bye.." << endl;
    exit(0); 
   }
   else {
   myinput = "Error: Bad input (" + myinput + "), Format: a+b | a-b | a*b | a/b"; 
      cout << myinput << endl;
   }
  }
 }

 return 0;
}

Calc.h

#pragma once
class Calculator
{
public:
 double Calculate(double x, char oper, double y);
};

Calc.cpp

#include "Calc.h"
 
double Calculator::Calculate(double x, char oper, double y)
{
 switch (oper)
 {
 case '+':
  return x + y;
 case '-':
  return x - y;
 case '*':
  return x * y;
 case '/':
  return x / y;
 default:
  return 0.0;
 }
}