// Probability that n bit number has less than k bits when P(1) = f.
// Print from k = 0 thru n.
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
typedef double R;
typedef long unsigned int L;
int main(int argc, char * * argv){
  if(argc != 3) exit(printf("int and float args %d\n", argc));
  int n = atoi(argv[1]);
  R f1 = atof(argv[2]), f0 = 1.-f1, fr = f1/f0, sm = 0; R cc = 0;
  {R t = 1, cn = 1; {int j=n; while(j--) {t *= f0; cn *= 0.5;}}
   int g = n, h = 0;
   if(t == 0.) exit(printf("Underflow\n"));
   {int j = n+1, j1=1; while(j--) {
     printf("%3d %8.5f %8.5f %8.5f %4.1f\n",
        h, t, sm, cc, log((0x1P64)*cc)/log(2));
     cc += cn; cn *= j; cn /= j1++;
     sm += t; ++h; t *= fr*g/h; --g;}}}
printf("ultimately: %9.7f %9.7f\n", sm, cc);
return 0;}