C / C++ / MFC

Calin Cali wrote:

Usually I don`t try to compile wild guesses.

Quote:

Well, you should because:

int Class::* pm = &Class::m;         // pointer to member data "int m"
int (Class::* pf)(int) = &Class::f;  // pointer to member function "int f(int)"
Class c, *k;
c.*pm = 1;        // c.m = 1;
n = c.*pf(0);     // n = c.f(0);
k->.pm = 2;       // k->m = 2;
n = (k->*pf)(0);  // n = k->f(0);  note that ->* requires parentheses

#include <stdio.h>
#include <stddef.h>
#include <stdbool.h>

bool uint2binstr(unsigned value, char output[], size_t output_size)
{
  unsigned v = value;
  unsigned bits = 0;
  while ( v )
  {
    v >>= 1;
    ++bits;
  }
  if ( ! bits ) ++bits;

  if ( output_size > bits )
  {
    output[bits] = '\0';
    while (bits)
    {
      --bits;
      output[bits] = (value & 1) + '0';
      value >>= 1;
    }
    return true;
  }
  return false;
}

enum { N = 33 }; // assuming 'unsigned' is 32 bits

int main()
{
  char out[N];

  unsigned a[] = { 0, 1, 128, 192, 65535, 65536, -1 };

  for (size_t n=0; n<sizeof(a)/sizeof(a[0]); ++n)
  {
    if ( uint2binstr(a[n], out, N) )
    {
      printf("success: '%u' decimal is '%s' binary\n", a[n], out);
    }
    else
    {
      printf("failed to represent '%u' in binary\n", a[n]);
    }
  }
  return 0;
}

enum GridOccupant {EMPTY, PREY, PREDATOR};
GridOccupant Grid[m][n] = {EMPTY};