TB's proposed coin flip game

#include <stdio.h>
#include "utilfun.h"

int
main( int argc, char *argv[] ) {

  int mm, nn;
  int numwon, numlost;
  int tt, ttall, hhall;
  int ii, jj;
  double fract, fractavg;

  seedrand(); // seed random number generator with epoch elapsed time

  mm = 1e6; // number of games to simulate
  nn = 1e4; // number of trials to simulate

  ttall = 0;
  hhall = 0;
  numwon = 0;
  numlost = 0;
  fractavg = 0.0;

  printf("\n");
  printf("%20.0e number of games to play\n", (double) mm);
  printf("%20.0e number of trials per game\n", (double) nn);
  printf("\n");
  printf("Simulating...\n");
  printf("\n");
  fflush(stdout);

  for ( ii = 0; ii < mm; ++ii ) {
    fract = 0.0; // fraction of tails
    tt = 0;      // number of tails flipped
    for ( jj = 0; jj < nn; ++jj ) {
      while ( ranf() < 0.5 ) // ranf() -> [0,1) uniform; flip until heads
        ++tt;  // while flipping tails
    } // for jj
    ttall += tt;
    hhall += nn; // one head flipped per trial
    fract += (double) tt / (tt + nn); // fraction of tails flipped
    fractavg += fract;
    if ( fract < 0.5 ) ++numwon;  // guess stop on heads
    if ( fract > 0.5 ) ++numlost; // guess stop on tails
  } // for ii

  fractavg /= mm;

  printf("%20.12e average fraction T/(T+H)\n", fractavg);
  printf("%20d total number of tails flipped\n", ttall);
  printf("%20d total number of heads flipped\n", hhall);
  printf("%20d number won by strategy guesser\n", numwon);
  printf("%20d number undecided by strategy guesser\n", mm - numwon - numlost);
  printf("%20d number lost by strategy guesser\n", numlost);
  printf("\n");

  return(0);
} // main