/* shia2.c - Don Yang (uguu.org)

   02/17/03
                                                                           */

#include<stdio.h>
#include<math.h>


int main(int u, char **v)
{
   int s, h, i, a, _[256];
   unsigned char t[8192];
   double e, n;
   FILE *m;

   if( u < 2 )
   {
      printf("%s <filename> [...]\n", *v);
   }
   else
   {
      for(a = 1; a < u; a++)
      {
         if( (m = fopen(v[a], "rb")) )
         {
            for(h = i = 0; i < 256; _[i++] = 0);
            for(; !feof(m); h += s)
            {
               if( !(s = fread(t, 1, 8192, m)) )
                  break;
               for(i = 0; i < s; _[t[i++]]++);
            }
            fclose(m);
            for(e = i = 0; i < 256; i++)
               if( _[i] )
               {
                  n = _[i] / (double)h;
                  e -= n * log(n) / log(2);
               }
            printf("%s: %f bits\n", v[a], e);
         }
      }
   }
   return 0;
}