#include <iostream>
#include <cmath>
#include <cctype>
 
using namespace std;
 
int main()
{
    char word;
	int count = 0;
 
 
    cout << "To stop this program enter %." << endl;
 
    cout << "Enter a telephone phrase followed by the '$' sign: ";                 
    cin >> word;                      
    cout << endl;
	word = static_cast<char>(toupper(word));
 
 
    while (word != '%')
    {               
		cout << "The corresponding telephone number is: ";
 
		while (word != '$')
		{
			for (count = 1; count <= 7; count++)
			{
            switch (word)                     
            {
            case 'A':
            case 'B':
            case 'C':
                cout << "2";             
                break;                            
            case 'D':
            case 'E':
            case 'F':
                cout << "3";          
                break;                      
            case 'G':
            case 'H':
            case 'I':
                cout << "4";         
                break;                          
            case 'J':
            case 'K':
            case 'L':
                cout << "5";         
                break;                    
            case 'M':
            case 'N':
            case 'O':
                cout << "6";            
                break;                      
            case 'P':
            case 'Q':
            case 'R':
            case 'S':
                cout << "7";            
                break;                        
            case 'T':
            case 'U':
            case 'V':
                cout << "8";             
                break;                           
            case 'W':
            case 'X':
            case 'Y':
            case 'Z':
                cout << "9";
				break;
			case ' ':
				cout << "";
				break;
            default:
                    cout << "Invalid input." << endl;
            }
			if (count == 3)
				cout << "-";
			cin >> word;
			word = static_cast<char>(toupper(word));
			}
		}
		cout << endl;
 
        cout << "Enter a telephone phrase followed by the '$' sign: ";
        cin >> word;
		word = static_cast<char>(toupper(word));
        cout << endl;
    }
 
    return 0;
}

while (word != '%')
{
  //...
 
  for (count = 1; word != '$' && count <= 7; count++)
  {
    //...
  }
 
  //...
}

while ( cin.get() != '\n' )
  ;