错误：我的每个函数和变量都没有在这个范围内声明(代码;;块，C++)

我是c++的新手，我写了我的第一个真正的程序(一个简单的四操作计算器)。当我编译它时，我得到了12个编译错误。我能够解决一些(缺少分号等)，但其中7个拒绝消失。错误和我的代码在这里:

错误:

    15 error: 'cout' was not declared in this scope
    15 error: 'endl' was not declared in this scope
    21 error: 'GetNumber' was not declared in this scope
    24 error: 'GetOperator' was not declared in this scope
    29 error: 'nAnswer' was not declared in this scope
    33 error: 'AskContinue' was not declared in this scope
    35 error: 'bContinue' was not declared in this scope

Main.cpp

    //Four-operation calculator
    //© Olli Utriainen 2013
    #include <iostream>
    //Header with functions GetNumber(), GetOperator() and AskContinue()
    #include "calculator.h"
    using namespace std;
    int main()
    {
        //Main loop's condition
        bool bContinue = false;
        cout << "Welcome to Olli's calculator!" << endl << endl;
        //Main loop
       do
        {
            cout << "Give first number" << endl;
            int nNumber1 = GetNumber();
            cout << "Give operator (+,-,*,/)" << endl;
            char cOperator = GetOperator();
            cout << "Give second number" << endl;
            int nNumber2 = GetNumber();
            nAnswer = nNumber1 + nNumber2;
            cout << nNumber1 << " " << cOperator << " " <<
            nNumber2 << " = " << nAnswer << endl;
            bContinue = AskContinue();
        } while (bcontinue);
        return 0;
    }

Headers.h

    //Headers for the calculator
    //© Olli Utriainen 2013
    #ifndef CALCULATOR_H_INCLUDED
    #define CALCULATOR_H_INCLUDED
   //Function for inputting numbers
   int GetNumber()
   //Function for inputting a mathematical operator (+,-,*,/)
   char GetOperator()
   //Function for asking Continue Yes/No
   bool AskContinue()
   #endif // CALCULATOR_H_INCLUDED

Functions.cpp

   //Functions for the calculator
   //© Olli Utriainen 2013
   #include <iostream>
   using namespace std;
   //Function for inputting numbers
   int GetNumber()
   {
       int nNumber
       cin >> nNumber;
       return nNumber
   }
   //Function for inputting a mathematical operator (+,-,*,/)
   int GetOperator()
   {
       char cOperator
       bool bValidOperator = false;
       //Do-while loop for checking if given operator
       //is valid (+,-,*,/). If invalid, bValidOperator
       //is changed to false ->loop will break and the
       //given operator is returned
       do
       {
           cin >> cOperator;
           if (cOperator == '+' || '-' || '*' || '/')
               {
                   bValidOperator = true;
               }
           else
               {
                   bValidOperator = false;
                   cout << "Invalid operator" << endl;
               }

       } while (!bValidOperator)
       return cOperator;
   }
   //Function for asking Continue Yes/No
   bool AskContinue()
   {
       cout << "New calculation? Y/N" << endl;
       bool bContinue = false;
       if (cin >> 'Y' || 'y')
           {
               bContinue = true;
           }
       if (cin >> 'N' || 'n')
           {
               bContinue = false;
           }
       return bcontinue;
   }