error C2679: binary '>>' no operator found for std::string.

[cegparamesh]

Hello friends,

When i try this simple program in Visual C++:

#include<iostream>
using namespace std;
int main()
{
	string s;
	cin>>s;

	cout<<s.c_str();

	return 0;
}

I get this error message:

error C2679: binary '>>' : no operator found which takes a right-hand 
operand of type 'std::string' (or there is no acceptable conversion)

The error message comes because of this line:

cin>>s;

I dont know how to solve this problem.
Please help me.

Thank You,
Paramesh.