#include <inttypes.h>
#include <stdio.h>

int main(int argc, char *argv[]) {
  struct point {
    union {
      struct {
        uint32_t x, y;
      };
      uint64_t u64;
    };
  };

  struct point a = {.x = 0x56, .y = 0x38};
  printf("%.16" PRIx64 "\n", a.u64);
  return 0;
}