2.61

/*
 * 2.61.c
 */

#include <stdio.h>
#include <assert.h>

int A(int x) {
  return !~x;
}

int B(int x) {
  return !x;
}

int C(int x) {
  return A(x | ~0xff);
}

int D(int x) {
  return B((x >> ((sizeof(int)-1) << 3)) & 0xff);
}

int main(int argc, char* argv[]) {
  int all_bit_one = ~0;
  int all_bit_zero = 0;

  assert(A(all_bit_one));
  assert(!B(all_bit_one));
  assert(C(all_bit_one));
  assert(!D(all_bit_one));

  assert(!A(all_bit_zero));
  assert(B(all_bit_zero));
  assert(!C(all_bit_zero));
  assert(D(all_bit_zero));

  // test magic number 0x1234ff
  assert(!A(0x1234ff));
  assert(!B(0x1234ff));
  assert(C(0x1234ff));
  assert(D(0x1234ff));

  // test magic number 0x1234
  assert(!A(0x1234));
  assert(!B(0x1234));
  assert(!C(0x1234));
  assert(D(0x1234));

  return 0;
}