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Convert letter to phone number using switch statement

footballboy (2)
I am trying to convert letter to corresponding telephone digits using only switch statement, but I got an infinite loop. It works if using if statement but I can only use switch Would you please help me detect the code?

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  #include <iostream>

using namespace std;

int main()
{
	char letter;

	cout << "Program to convert uppercase "
		<< "letters to their corresponding "
		<< "telephone digits." << endl;
	cout << "To stop the program enter #."
		<< endl;

	cout << "Enter a letter: ";
	cin >> letter;
	cout << endl;

	while (letter != '#')
	{
		cout << "The letter you enter is: " 
			<< letter << endl;
		cout << "The corresponding telephone digit is: ";

		switch (letter)
		{
		case 'A':
		case 'B':
		case 'C':
			cout << 2 << endl;
			break;
		case 'D':
		case 'E':
		case 'F':
			cout << 3 << endl;
			break;
		case 'G':
		case 'H':
		case 'I':
			cout << 4 << endl;
			break;
		case 'J':
		case 'K':
		case 'L':
			cout << 5 << endl;
			break;
		case 'M':
		case 'N':
		case 'O':
			cout << 6 << endl;
			break;
		case 'P':
		case 'Q':
		case 'R':
		case 'S':
			cout << 7 << endl;
			break;
		case 'T':
		case 'U':
		case 'V':
			cout << 8 << endl;
			break;
		case 'W':
		case 'X':
		case 'Y':
		case 'Z':
			cout << 9 << endl;
			break;
		default:
			{cout << "Invalid input." << endl;
		
			cout << "\nEnter another uppercase "
			<< "letter to find its "
			<< "corresponding telephone digit."
			<< endl;
			cout << "To stop the program enter #."
			<< endl;

			cout << "Enter a letter: ";
			cin >> letter;
			cout << endl;}
		}
	}

	return 0;

}
Smac89 (1727)
Use a do-while loop:

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cout << "Program to convert uppercase "
     << "letters to their corresponding "
     << "telephone digits." << endl;

do {
    cout << "To stop the program enter #.\n"

    cout << "Enter a letter: ";
    cin >> letter;

    cout << "The letter you enter is: " 
         << letter << endl
         << "The corresponding telephone digit is: ";

    switch() {...}

} while (letter != '#');
Last edited on
JLBorges (13770)
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#include <iostream>

using namespace std;

int main()
{
	char letter;

	cout << "Program to convert uppercase letters to their corresponding "
		  << "telephone digits.\nTo stop the program enter #.\n" ;

	cout << "Enter a letter: ";
	cin >> letter;
	cout << endl;

	while (letter != '#')
	{
		cout << "The letter you enter is: "
			<< letter << endl;
		cout << "The corresponding telephone digit is: ";

		switch (letter)
		{
		    case 'A':
		    case 'B':
		    case 'C':
			    cout << 2 << endl;
			    break;

                    // case ...

		    default:
                            cout << "Invalid input." << endl;

                } // end switch
        
                // this part should be outside the switch, but within the while loop
                cout << "\nEnter another uppercase letter to find its "
                     << "corresponding telephone digit.\nTo stop the program enter #.\n" ;
                cin >> letter;

        } // end while

} // end main()

footballboy (2)
Thank you for your help, I just got it. I suppose to put the curly bracket after default:, not after cout << endl. I was trying to use a do-while, thanks anyway
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