#include <math.h>

int main()
{
  float pLoseW,pLoseB;
  float p;
  float beta;
  int yourrating,theirrating;
  printf("Please input Playing as White (Lose) e.g. 89.33 :");
  scanf("%f", &pLoseW);
  printf("Please input Playing as Black (Lose) e.g. 89.93 :");
  scanf("%f",&pLoseB);
  printf("Please input Your rating: e.g. 25: ");
  scanf("%d", &yourrating);
  printf("Please input Their rating: e.g. 26: ");
  scanf("%d",&theirrating);
  pLoseW = pLoseW * 0.01;
  pLoseB = pLoseB * 0.01;
  p = abs(pLoseW - 0.5) > abs(pLoseB-0.5) ? pLoseB : pLoseW;
  if (p < 0.5) beta = (log(p) - log(0.5)) / (2*log(0.75));
  else beta = (log(0.5) - log(1-p)) / (2*log(0.75));
  printf("Beta is %f. Therefore the difference are about %f games. \n", beta, beta/ 0.045);
  printf("Your actual rating maybe: %f\n",
     abs(pLoseW - 0.5) > abs(pLoseB-0.5) ? yourrating - beta : theirrating + beta);
  exit(0);
}