I'm trying to make a program that asks the user if they wish to quit. but Dev-C++ is giving me this error:

27 C:\Dev-Cpp\GradeBook.cpp no match for 'operator>>' in 'std::cin >> q'

here's the code:

Code:
#include <iostream>
#include <string>
using namespace std;
class GradeBook
{
public:
       void displayMessage()
       {
        cout << "Welcome to the Grade Book!" << endl;
       }
};

int main()
{
 top:
 system("CLS");

 GradeBook myGradeBook;
 myGradeBook.displayMessage();

 string q[1000000];
 q[0] = "y";
 do
 {
  topOfLoop:
  cout << "\nDo you wish to quit? (y/n): ";
  cin >> q;
  if (q[0] == "n") goto top; 
  if (q[0] == "y") return 1;
  else 
       cout << "That's not a choice!\n\n";
       goto topOfLoop;
 }
 while (q[0] != "y");
 
 return 0;
}
I recently changed the array to a string array from a char array. The char array worked a little better but I'm trying to improve the program. Any help?