Adding numbers in C without "+"

c-array-adding.c

#include <stdio.h>

/* DISCLAIMER: THIS IS NOT MEANT TO BE USED IN REAL PROGRAMS */

int main(int argc, char ** argv)
{
  void * a = (void *)10;
  void * b = (void *)5;
  void * r;

  r = &(((char *)a)[(size_t)b]);
  printf("%i\n", (size_t)r);

  return 0;
}