you must have to include the String library

using namespace std;

int main() {

string name = "";
int age = 0;

cout << "What is you name?" << endl;
cin >> name;

cout << "How old are you?" << endl;
cin >> age;

printf("Hello, %s, nice to meet you. You have %i years right?", name.c_str(), age);

return 0;

}