// FieldDemo.cpp

#include <iostream>
#include <string>

using namespace std;

inline bool is_resource_field( const string& fld_name )
{
  const string& prefix = "PHONE";

  string::size_type n = fld_name.
  find_first_of(".");  // handle multi fields
  if (n == string::npos)  // not a multi value field or a primary multi value field
    return fld_name == prefix;
  else
    return fld_name.substr(0, n) == prefix;
}

int main()
{
  cout << is_resource_field("PHONE") << endl;
  cout << is_resource_field("PHONE.01") << endl;
  cout << is_resource_field("PHONE#") << endl;
  cout << is_resource_field("PHONE#.01") << endl;
}