Control Instructions problems
- 1. What will be the output of the program?
#include<stdio.h> int main() { int k, num = 30; k = (num < 10)? 100 : 200; printf("%d\n", num); return 0; }
Options- A. 200
- B. 30
- C. 100
- D. 500 Discuss
Correct Answer: 30
- 2. What will be the output of the program?
#include<stdio.h> int main() { int a=0, b=1, c=3; *((a)? &b : &a) = a? b : c; printf("%d, %d, %d\n", a, b, c); return 0; }
Options- A. 0, 1, 3
- B. 1, 2, 3
- C. 3, 1, 3
- D. 1, 3, 1 Discuss
Correct Answer: 3, 1, 3
Explanation:
Step 2: *((a) ? &b : &a) = a ? b : c; The right side of the expression(a?b:c) becomes (0?1:3). Hence it return the value '3'.
The left side of the expression *((a) ? &b : &a) becomes *((0) ? &b : &a). Hence this contains the address of the variable a *(&a).
Step 3: *((a) ? &b : &a) = a ? b : c; Finally this statement becomes *(&a)=3. Hence the variable a has the value '3'.
Step 4: printf("%d, %d, %d\n", a, b, c); It prints "3, 1, 3".
- 3. What will be the output of the program?
#include<stdio.h> int main() { int x = 3; float y = 3.0; if(x == y) printf("x and y are equal"); else printf("x and y are not equal"); return 0; }
Options- A. x and y are equal
- B. x and y are not equal
- C. Unpredictable
- D. No output Discuss
Correct Answer: x and y are equal
Explanation:
Step 2: float y = 3.0; here variable y is an float type and initialized to '3.0'
Step 3: if(x == y) here we are comparing if(3 == 3.0) hence this condition is satisfied.
Hence it prints "x and y are equal".
- 4. What will be the output of the program?
#include<stdio.h> int main() { int i=4; switch(i) { default: printf("This is default\n"); case 1: printf("This is case 1\n"); break; case 2: printf("This is case 2\n"); break; case 3: printf("This is case 3\n"); } return 0; }
Options- A. This is default
This is case 1 - B. This is case 3
This is default - C. This is case 1
This is case 3 - D. This is default Discuss
Correct Answer: This is default
This is case 1
Explanation:
In default statement there is no break; statement is included. So it prints the case 1 statements. "This is case 1".
Then the break; statement is encountered. Hence the program exits from the switch-case block.
- 5. What will be the output of the program?
#include<stdio.h> int main() { int a = 500, b = 100, c; if(!a >= 400) b = 300; c = 200; printf("b = %d c = %d\n", b, c); return 0; }
Options- A. b = 300 c = 200
- B. b = 100 c = garbage
- C. b = 300 c = garbage
- D. b = 100 c = 200 Discuss
Correct Answer: b = 100 c = 200
Explanation:
Step 1: if(!a >= 400)
Step 2: if(!500 >= 400)
Step 3: if(0 >= 400)
Step 4: if(FALSE) Hence the if condition is failed.
Step 5: So, variable c is assigned to a value '200'.
Step 6: printf("b = %d c = %d\n", b, c); It prints value of b and c.
Hence the output is "b = 100 c = 200"
- 6. What will be the output of the program?
#include<stdio.h> int main() { int a = 300, b, c; if(a >= 400) b = 300; c = 200; printf("%d, %d, %d\n", a, b, c); return 0; }
Options- A. 300, 300, 200
- B. Garbage, 300, 200
- C. 300, Garbage, 200
- D. 300, 300, Garbage Discuss
Correct Answer: 300, Garbage, 200
Explanation:
Step 2: if(a >= 400) means if(300 >= 400). Hence this condition will be failed.
Step 3: c = 200; here variable c is initialized to '200'.
Step 4: printf("%d, %d, %d\n", a, b, c); It prints "300, garbage value, 200". because variable b is not initialized.
- 7. What will be the output of the program?
#include<stdio.h> int main() { char str[]="C-program"; int a = 5; printf(a >10?"Ps\n":"%s\n", str); return 0; }
Options- A. C-program
- B. Ps
- C. Error
- D. None of above Discuss
Correct Answer: C-program
Explanation:
Step 2: int a = 5; here variable a contains "5".
Step 3: printf(a >10?"Ps\n":"%s\n", str); this statement can be written as
if(a > 10)
{
printf("Ps\n");
}
else
{
printf("%s\n", str);
}
Here we are checking a > 10 means 5 > 10. Hence this condition will be failed. So it prints variable str.
Hence the output is "C-program".
- 8. What will be the output of the program?
#include<stdio.h> int main() { char j=1; while(j < 5) { printf("%d, ", j); j = j+1; } printf("\n"); return 0; }
Options- A. 1 2 3 ... 127
- B. 1 2 3 ... 255
- C. 1 2 3 ... 127 128 0 1 2 3 ... infinite times
- D. 1, 2, 3, 4 Discuss
Correct Answer: 1, 2, 3, 4
- 9. What will be the output of the program?
#include<stdio.h> int main() { int i=3; switch(i) { case 1: printf("Hello\n"); case 2: printf("Hi\n"); case 3: continue; default: printf("Bye\n"); } return 0; }
Options- A. Error: Misplaced continue
- B. Bye
- C. No output
- D. Hello Hi Discuss
Correct Answer: Error: Misplaced continue
Explanation:
- 10. What will be the output of the program?
#include<stdio.h> int main() { int x=1, y=1; for(; y; printf("%d %d\n", x, y)) { y = x++ <= 5; } printf("\n"); return 0; }
Options- A. 2 1
3 1
4 1
5 1
6 1
7 0 - B. 2 1
3 1
4 1
5 1
6 1 - C. 2 1
3 1
4 1
5 1 - D. 2 2
3 3
4 4
5 5
Discuss
Correct Answer: 2 1
3 1
4 1
5 1
6 1
7 0
More in C Programming:
Programming
Copyright ©CuriousTab. All rights reserved.