[user02@FC4 Lesson09]$ cat -n get_yn.cpp

   1  #include <iostream>
   2  using namespace std;
   3
   4  int main()
   5  {
   6     int done = 0;    // Set to true when Y or N is encountered
   7     char letter;
   8
   9     while (! done)
  10       {
  11          cout << "\nType Y or N and press Enter to continue: ";
  12          cin >> letter;
  13
  14          if ((letter == 'Y') || (letter == 'y'))
  15             done = 1;
  16          else if ((letter == 'N') || (letter == 'n'))
  17             done = 1;
  18          else
  19             cout << '\a';   // Sound the speakers bell for
  20                             // invalid character
  21       }
  22     cout << "The letter you typed was " << letter << endl;
  23
  24     return 0;
  25  }

[user02@FC4 Lesson09]$ g++ -o get_yn get_yn.cpp
[user02@FC4 Lesson09]$ ./get_yn

Type Y or N and press Enter to continue: y
The letter you typed was y
[user02@FC4 Lesson09]$ ./get_yn

Type Y or N and press Enter to continue: a

Type Y or N and press Enter to continue: No
The letter you typed was N
[user02@FC4 Lesson09]$