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a) the character a b) 97 (ASCII code of a) c) some arbitrary number d) it may crash/will be unpredictable e) it won't compile What will this code print: printf("%i", 'a'); 1 a) the character a b) 97 (ASCII code of a) c) some arbitrary number d) it may crash/will be unpredictable e) it won't compile What will this code print: printf("%c", 'a'); 2 a) the character a b) 97 (ASCII code of a) c) some arbitrary number d) it may crash/will be unpredictable e) it won't compile What will this code print: printf("%c"); 3 a) the character a b) 97 (ASCII code of a) c) some arbitrary number d) it may crash/will be unpredictable e) it won't compile What will this code print: printf(); 4 a) the character a b) 97 (ASCII code of a) c) some arbitrary number d) it may crash/will be unpredictable e) it won't compile What will this code print: printf("%i", "a"); 5 What will this code do: *int main(void) { char s; fgets(s, 61, stdin); printf("%s", s); } a) accept input, print the first 60 characters b) accept input, print arbitrary text c) will not accept input, print arbitrary text d) it may crash/will be unpredictable e) it won't compile 6
What will this code do: int main(void) { char s[61]; fgets(s, sizeof(s), stdin); printf("%s", s); } a) accept input, print the first 60 characters b) accept input, print arbitrary text c) will not accept input, print arbitrary text d) it may crash/will be unpredictable e) it won't compile 7 What will this code do (assume malloc doesn't fail): *int main(void) { char s = malloc(61); fgets(s, sizeof(s), stdin); printf("%s", s); } a) accept input, print user's input, up to the first 60 characters b) accept input, print arbitrary text c) it may crash/will be unpredictable d) it won't compile e) none of the above (^8) What will this code do (assume malloc doesn't fail): *int main(void) { char s = malloc(61); fgets(s, 61, stdin); printf("%s", s); } a) accept input, print the first 60 characters b) accept input, print arbitrary text c) it may crash/will be unpredictable d) it won't compile e) none of the above 9 a)sizeof(s)/sizeof(s[0]) b)sizeof(s) c)strlen(s) d)sizeof(s)/sizeof(char) e) None of the above How can we find the length of string s? *void example(char s); 10 How can we find the # of elements in arr? void example(int arr[]); a)sizeof(arr)/sizeof(arr[0]) b)sizeof(arr) c)strlen(arr) d)sizeof(arr)/sizeof(int) e) None of the above 11 How can we find the # of elements in arr? int arr[SOME_NUMERIC_CONSTANT]; a)sizeof(arr)/sizeof(arr[0]) b)sizeof(arr) c)strlen(arr) d)sizeof(arr)/sizeof(int) e) None of the above 12
19 a) fopen("example.txt", "w"); b) fopen("example.txt",'w'); c) fopen("example.txt","r+"); d) fopen("example.txt","a"); e) None of the above If you'd like to write to a file, appending to the end if it already exists, which of the following should you use: 20 a) fseek(f, 200, SEEK_END); b) fseek(f, 200, SEEK_SET); c) fseek(f, 200, SEEK_BEGIN); d) fseek(f, 200, SEEK_CUR); e) None of the above Which of the following will ensure that a subsequent fread from FILE pointer f will read from the last 200 bytes of the file: 21 a) I think I know b) I know what that is, but I'm not sure why we need it. c) What's a free function? Why do we have a free function? 22 a) I think I know b) I know what one does, but I don't think they're different c) What's a ++? What's the difference between i++ and ++i 23 a) b) c) either is fine d) both are erroneous Which of the following is a valid implementation of a linked list node: *struct node { int value; struct node next; }; struct node { int value; struct node next; }; 24 a) Yes b) No c) I don't know Is there anything wrong with this code to resize a malloc'd character buffer? **char resize(char old, int size) { char ret = malloc(size); memcpy(ret, old, sizeof(old)); return ret; } / called elsewhere: / arr = resize(arr, old_size + 10);
25 a) 0xFFFF b) 0xFF c) 0xF0FF d) 0xF0F e) None of the above 0xF00F & 0xFF | 0xF0F ^ 0x000F == 26 a) x = x >> n b) x = x ^ (1 << n) c) x = x >> (n-1) d) x = x ^ (1 << (n-1)) e) None of the above Which of the following will toggle the nth^ least- significant bit in int x 27 a) x = x >> n b) x = (1 & x) >> n c) x = x >> (n-1) d) x = (1 & x) >> (n-1) e) None of the above Which of the following will return 1 if the nth least-significant bit in int x is 1, 0 otherwise 28 a) global b) static local c) static global d) automatic local e) None of the above What kind of variable has local scope, but global lifetime 29 a) 8 b) 4 c) 16 d) 2 How many possible values can s.x take? struct foo { int x:3, y:2, z:1}; struct foo s; 30 a)1, 2 b)2, 1 c) In may crash/will be unpredictable d) It will not compile/will give warnings and not do what it's supposed to do What will this program print: void swap(int a, int b) { int t = a; a = b; b = t; } int main() { int a = 1, b = 2; swap(a, b); printf("%d, %d\n", a, b); }
37 a)1, 2 b)2, 1 c) In may crash/will be unpredictable d) It will not compile/will give warnings and not do what it's supposed to do What will this program print: **struct foo { int v; }; void swap(struct foo a, struct foo b) { int t = a->v; a->v = b->v; b->v = t; } int main() { struct foo a = {1}, b = {2}; swap(&a, &b); printf("%d, %d\n", a.v, b.v); }
