161. What is the output of: printf("%d", (int(*)[2]){1,2}[0][1]);
- a) 1
- b) 2
- c) Compilation error
- d) Undefined behavior
Answer: B - This compound literal creates a pointer to array[2] and accesses element [0][1].
162. Which of these is NOT a valid C11 atomic compare operation?
- a) atomic_compare_exchange_strong()
- b) atomic_compare_exchange_weak()
- c) atomic_compare_swap()
- d) (No incorrect options - all are valid)
Answer: C - atomic_compare_swap() doesn't exist (correct are compare_exchange_strong/weak).
163. What is the purpose of the 'mtx_timedlock()' function?
- a) Lock mutex with timeout
- b) Lock mutex recursively
- c) Initialize timed mutex
- d) Destroy mutex
Answer: A - mtx_timedlock() attempts to lock mutex with timeout.
164. What is the output of: printf("%d", 1 ^ 2 & 3);
- a) 0
- b) 1
- c) 2
- d) 3
Answer: D - & has higher precedence: 2&3=2, then 1^2=3.
165. Which function is used to query floating-point sign in C99?
- a) signbit()
- b) fp_sign()
- c) fsign()
- d) getsign()
Answer: A - signbit() macro from math.h tests floating-point sign.
166. What is the value of: (int(*)[2]){1,2} + 1
- a) 1
- b) 2
- c) Pointer to next array
- d) Compilation error
Answer: C - Pointer arithmetic advances by sizeof(int[2]) bytes.
167. Which of these is NOT a valid C11 thread error code?
- a) thrd_nomem
- b) thrd_timedout
- c) thrd_busy
- d) thrd_locked
Answer: D - thrd_locked doesn't exist (correct are nomem/timedout/busy).
168. What is the output of: printf("%d", 1 + 2 * 3 - 4);
- a) 1
- b) 3
- c) 5
- d) 7
Answer: B - * first: 2*3=6, then 1+6-4=3.
169. What is the purpose of the 'mtx_plain' constant?
- a) Non-recursive mutex
- b) Recursive mutex
- c) Timed mutex
- d) Shared mutex
Answer: A - mtx_plain creates non-recursive mutex (vs mtx_recursive).
170. What is the output of: printf("%d", 1 << 30 >> 30); (32-bit int)
- a) 0
- b) 1
- c) Undefined behavior
- d) Implementation defined
Answer: B - 1<<30 creates 0x40000000, >>30 brings it back to 1.
171. Which function is used to find wide character in memory block?
- a) wmemchr()
- b) wchr()
- c) wfind()
- d) wstrchr()
Answer: A - wmemchr() searches for wide character in memory.
172. What is the value of: (int(*)[2]){1,2}[0][0] = 3
- a) 1
- b) 2
- c) 3
- d) Compilation error
Answer: C - Array elements from compound literals are modifiable.
173. Which of these is NOT a valid C11 mutex type?
- a) mtx_plain
- b) mtx_recursive
- c) mtx_timed
- d) mtx_shared
Answer: D - mtx_shared doesn't exist (correct are plain/recursive/timed).
174. What is the output of: printf("%d", 1 ? 2 + 3 : 4);
- a) 2
- b) 3
- c) 5
- d) Compilation error
Answer: C - 1 is true → evaluates 2+3=5 (ternary has lower precedence than +).
175. What is the purpose of the 'mtx_recursive' constant?
- a) Recursive mutex
- b) Non-recursive mutex
- c) Timed mutex
- d) Shared mutex
Answer: A - mtx_recursive creates mutex that can be locked multiple times by same thread.
176. What is the output of: printf("%d", 1 << 3 << 2);
- a) 8
- b) 16
- c) 32
- d) 64
Answer: C - Left-associative: (1<<3)=8, then 8<<2=32.
177. Which function is used to compare wide character memory blocks?
- a) wmemcmp()
- b) wcmp()
- c) wmcmp()
- d) wstrcmp()
Answer: A - wmemcmp() compares wide character memory blocks.
178. What is the value of: (int(*)[2]){1,2}[0][1] = 3
- a) 1
- b) 2
- c) 3
- d) Compilation error
Answer: C - Array elements from compound literals are modifiable.
179. Which of these is NOT a valid C11 mutex initialization flag?
- a) mtx_plain
- b) mtx_timed
- c) mtx_shared
- d) mtx_recursive
Answer: C - mtx_shared doesn't exist (correct are plain/timed/recursive).
180. What is the output of: printf("%d", 0 ? 1 + 2 : 3 + 4);
- a) 3
- b) 5
- c) 7
- d) Compilation error
Answer: C - 0 is false → evaluates 3+4=7 (ternary has lower precedence than +).