#include <iostream>
#include <string>

using namespace std;

int main( )
{
   string credit_card( "4578 9906 512 6661" );
   cout << "Credit card number: " << credit_card;

   // equivalent of strset()
   credit_card.assign( credit_card.length(), '*' );
   cout << "\nMore secure display of credit card number: " << credit_card;
}
