Using Input String to Call Function

#include <iostream>
#include <string>
using namespace std;

void male()
  {
  cout << "I'm a man.\n";
  }

void female()
  {
  cout << "I'm a woman.\n";
  }

struct
  {
  (void)(*fn)();
  const char* key;
  }
function_lookup_table[] =
  {
  { &male,   "male"   },
  { &female, "female" },
  { NULL,    NULL     }
  };

bool lookup_and_call( const string& name )
  {
  for (int i = 0; function_lookup_table[ i ].fn; i++)
    if (name == function_lookup_table[ i ].key)
      {
      (*(function_lookup_table[ i ].fn))();
      return true;
      }
  return false;
  }

int main()
  {
  string users_gender;
  cout << "Enter male or female> " << flush;
  getline( cin, users_gender );
  if (!lookup_and_call( users_gender ))
    {
    cout << "What?\n";
    }
  return 0;
  }