# include <cstdlib>
# include <iostream>
# include <ctime>

using namespace std;

int main ( )
//
//  DUEL_ONCE simulates a duel between players of equal accuracy.
//  The players alternate until one has been hit.
//  For this situation, with accuracies of 1/2, the first player has a 2/3 
//  chance of surviving, simply by going first.
//
//  I had to use SRAND48() and DRAND48(), because generating a few real random
//  numbers with SRAND() seeded by TIME() and r = rand()/RAND_MAX ends up
//  producing essentially the same random real numbers each time!  After a few
//  calls, things improve, but for this example that's too late.
//
{
  int seed, shot, winner;
//
//  Initialize the random number generator.
//
  seed = time ( 0 );
  srand48 ( seed );

  winner = 0;
  shot = 0;
  
  while ( winner == 0 )
  {
    shot = shot + 1;
    if ( drand48 ( ) <= 0.5 )
    {
      winner = 1;
      break;
    }
    shot = shot + 1;
    if ( drand48 ( ) <= 0.5 )
    {
      winner = 2;
      break;
    }
  }
  cout << "Duel was won by " << winner << " after " << shot << " shots.\n";
  return 0;
}