#include <assert.h>

int main() {
  int foo;

  foo = 42;

  /* Delete bit 5 */
  foo &= ~(1 << 5);
  assert(foo == 10);
  foo &= ~(1 << 5);
  assert(foo == 10);

  /* Set bit 5 again */
  foo |= (1 << 5);
  assert(foo == 42);
  foo |= (1 << 5);
  assert(foo == 42);

  /* Set bit 0 */
  foo |= (1 << 0);
  assert(foo == 43);

  /* Delete bit 0 */
  foo &= ~(1 << 0);
  assert(foo == 42);

  /* Toggle bit 5 */
  foo ^= (1 << 5);
  assert(foo == 10);
  foo ^= (1 << 5);
  assert(foo == 42);
}