Thread: switch statement issues...(undeclared identifiers)

I am trying to work this switch statement into my future reference program.

Code:

char playSong;
    std::cout << "Which is best? La, Da, or This..." << endl;
    std::cin >> playSong;
    switch (playSong){
        case L:
            std::cout << "Lalalalala" << endl;
            break;
        case D:
            std::cout << "Da da da" << endl;
            break;
        case T:
            std::cout << "This love has taken it's toll..." << endl;
            break;
        default:
            std::cout << "Your done." << endl;
            break;
    }

The error is saying that L, D, and T are undeclared identifiers...what do I do to solve that?