C++ string Accessing characters in a string

#include <iostream>
#include <string>
#include <locale>

using std::string;

int main() {/* www. ja va2  s  .c o m*/
  string text;                                   // Stores the input
  std::cout << "Enter a line of  text:\n";
  std::getline(std::cin, text);                  // Read a line including spaces

  int vowels {};                                 // Count of vowels
  int consonants {};                             // Count of consonants
  for(int i {} ; i<text.length() ; ++i)
  {
    if(std::isalpha(text[i]))                    // Check for a letter
      switch(std::tolower(text[i]))              // Convert to lowercase
      {
        case 'a': case 'e': case 'i': case 'o': case 'u':
          ++vowels;
          break;

        default:
          ++consonants;
          break;
    }
  }

  std::cout << "Your input contained " << vowels << " vowels and "
            << consonants << " consonants." << std::endl;
}