% Title: Obligatorisk oppgave - IN3230/IN4230 - H?st 2024

% Author: Kristjon Ciko kristjoc@ifi.uio.no

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% Name:

% Username:

% Submission date:

% Course code:

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1. What does this function return?

1  int f1(int a, int b) {
2      return (a>b?a:b);
3  }

A. compiler error

B. the smaller value of the two passed parameters

C. the greater value of the two passed parameters

D. runtime error

Answer:

Explanation:

2. Which is not a correct way to declare a string variable?

A. char str = "Hei IN3230";

B. char *str = "Hei IN3230";

C. char str[20] = {'H', 'e', 'i', ' ', 'I', 'N', '3', '2', '3', '0', '\0'};

D. char str[] = "Hei IN3230";

Answer:

Explanation:

3. Which function do you use to deallocate memory?

A. dalloc()

B. release()

C. free()

D. dealloc()

Answer:

Explanation:

4. In which segment does dynamic memory allocation take place?

A. BSS segment

B. stack

C. data segment

D. heap

Answer:

Explanation:

5. What is not a valid command with this declaration?

1 char *string[20] = {"one", "two", "three"};

A. printf("%c", string[1][2]);

B. printf("%s", string[1][2]);

C. printf(string[1]);

D. printf("%s", string[1]);

Answer:

Explanation:

6. Void pointer vptr is assigned the address of float variable g. What is a valid way to dereference vptr to assign its pointed value to a float variable named f later in the program?

1  float g;
2  void *vptr = &g;

A. f = *(float)vptr;

B. f = (float)*vptr;

C. f = *(float *)vptr;

D. f = (float *)vptr;

Answer:

Explanation:

7. What does the strcmp(str1, str2); function return?

A. ? true (1) if str1 and str2 are the same ? NULL if str1 and str2 are not the same

B. ? 0 if str1 and str2 are the same ? a negative number if str1 is less than str2 ? a positive number if str1 is greater than str2

C. ? true (1) if str1 and str2 are the same ? false (0) if str1 and str2 are not the same

D. ? 0 if str1 and str2 are the same ? a negative number if str2 is less than str1 ? a positive number if str2 is greater than str1

Answer:

Explanation:

8. How many times does the code inside the while loop get executed in this program?

1  void main() {
2  int x=1;
3      while (x++<100) {
4          x*=x;
5          if (×<10) continue;
6          if (x>50) break;
7      }
8  }

A. 5

B. 50

C. 100

D. 3

Answer:

Explanation:

9. Which choice is an include guard for the header file mylib.h?

A.

#ifndef MYLIB_H
#define MYLIB_H
//mylib.h content
#endif /* MYLIB_H */

B.

#define MYLIB_H
#include "mylib.h"
#undef MYLIB_H

C.

#ifdef MYLIB_H
#define MYLIB_H
//mylib.h content
#endif /* MYLIB_H */

D.

#ifdef MYLIB_H
#undef MYLIB_H
//mylib.h content
#endif /* MYLIB_H */

Answer:

Explanation:

10. What is the sequence printed by the following program?

1  #include <stdio.h>
2
3  void print_3_ints(int *ip)
4  {
5      printf("%d %d %d ", ip[0], ip[1], ip[2]);
6  }
7
8
9  int main(void)
10 {
11     int array[] = { 5, 23, 119, 17 };
12     int *p, *q, d;
13
14     p = array; q = p + 1;
15
16     print_3_ints(q);
17
18     d = *(p++);
19     printf("%d ", d);
20
21     d = ++(*p);
22     printf("%d ", d);
23
24     printf("\n");
25     return 0;
26 }

A. 23 119 17 5 24

B. 23 119 17 23 24

C. 24 120 18 6 25

D. 25 120 18 25 26

Answer:

Explanation:

11. What is the output of the following program?

1  #include <stdio.h>
2
3  void func(int *ptr)
4  {
5      *ptr = 30;
6  }
7
8  int main()
9  {
10     int y = 20;
11     func(&y);
12     printf("%d\n", y);
13
14     return 0;
15 }

A. 20

B. 30

C. Compiler error

D. Runtime error

Answer:

Explanation:

12. What is the output of the following program?

1  #include <stdio.h>
2  #include <stdlib.h>
3
4  int main()
5  {
6      int i, numbers[1];
7      numbers[0] = 15;
8      free(numbers);
9      printf("Stored integers are ");
10     printf("numbers[%d] = %d ", 0, numbers[0]);
11
12     return 0;
13 }

A. Runtime error

B. Compilation error

C. 0

D. Garbage value

Answer:

Explanation:

13. What is the error of this program?

1  #include <stdio.h>
2  #include <stdlib.h>
3  #include <string.h>
4
5  int main()
6  {
7      char *ptr;
8      *ptr = (char)malloc(8);
9      strcpy(ptr, "RAM");
10     printf("%s", ptr);
11     free(ptr);
12     return 0;
13 }

A. Error in strcpy() statement

B. Error in *ptr = (char)malloc(8);

C. Error in free(ptr);

D. No error

Answer:

Explanation:

14. What is the output of the following program?

1  #include <stdio.h>
2
3  struct result{
4      char sub[20];
5      int marks;
6  };
7
8  int main()
9  {
10     struct result res[] = {
11          {"IN3230",100},
12    		{"IN4230",90},
13    		{"Norsk",85}};
14
15     printf("%s ", res[1].sub);
16
17     printf("%d\n", (*(res+2)).marks);
18
19     return 0;
20 }

A. IN3230 100

B. IN4230 85

C. IN4230 90

D. Norsk 100

Answer:

Explanation:

15. What is the output of this code snippet?

1  void main()
2  {
3      struct bitfields {
4          int bits_1: 2;
5          int bits_2: 9;
6          int bits_3: 6;
7          int bits_4: 1;
8      }bit;
9
10     printf("%d\n", sizeof(bit));
11 }

A. 2

B. 3

C. 4

D. 0

Answer:

Explanation:

16. In which line is the BUG in the following program?

1  #include <stdio.h>
2
3  int main()
4  {
5      int a, *ptr;
6      a = 25;
7      *ptr = a + 5;
8
9      return 0;
10 }

Answer:

Explanation:

17. In which line is the BUG in the following program?

1  #include <stdio.h>
2  struct var {
3      int value;
4      int *address;
5  };
6
7  int main()
8  {
9      struct var y;
10     int a = 10;
11     int *ptr = &a;
12
13     y.value = *ptr;
14     (&y)->address = ptr;
15
16     printf("value %d\n", y.value);
17     printf("address %p\n", y->address);
18     return 0;
19  }

Answer:

Explanation:

18. What are the two mistakes in the following program?

1   #include <stdio.h>
2
3   int main () {
4       const char src[8] = "IN3230";
5       char dest[8];
6
7       strcpy(dest, "Hellllo");
8
9       memcpy(dest, src, strlen(src));
10
11      printf("%s\n", dest);
12      return(0);
13  }

Answer:

Explanation: