Data Types Trivia Quiz

1. Which of the following is not a valid declaration in C?

1. short int x;

2. signed short x;

3. short x;

4. unsigned short x;

3 and 4

2

1

All are valid

All of the given options are valid declarations in C. Option 1 declares a short integer variable named x. Option 2 declares a signed short integer variable named x. Option 3 declares a variable named x of type short. Option 4 declares an unsigned short integer variable named x. Therefore, all the given options are valid declarations in C.

Explanation

All of the given options are valid declarations in C. Option 1 declares a short integer variable named x. Option 2 declares a signed short integer variable named x. Option 3 declares a variable named x of type short. Option 4 declares an unsigned short integer variable named x. Therefore, all the given options are valid declarations in C.

2. Predict the output of following program. Assume that the numbers are stored in 2's complement form.

#include<stdio.h> int main() { unsigned int x = -1; int y = ~0; if(x == y) printf("same"); else printf("not same"); return 0; }

Same

Not Same

The program initializes an unsigned integer variable "x" with the value -1. In 2's complement form, -1 is represented as a sequence of all 1's. The program also initializes an integer variable "y" with the bitwise complement of 0, which is also a sequence of all 1's. In the if statement, it checks if "x" is equal to "y". Since both "x" and "y" have the same value of all 1's, the condition is true and the program prints "same". Therefore, the output of the program is "Same".

Explanation

The program initializes an unsigned integer variable "x" with the value -1. In 2's complement form, -1 is represented as a sequence of all 1's. The program also initializes an integer variable "y" with the bitwise complement of 0, which is also a sequence of all 1's. In the if statement, it checks if "x" is equal to "y". Since both "x" and "y" have the same value of all 1's, the condition is true and the program prints "same". Therefore, the output of the program is "Same".

3. In C, sizes of an integer and a pointer must be same.

True

False

In C, the sizes of an integer and a pointer are not required to be the same. The size of an integer is typically 4 bytes, while the size of a pointer can vary depending on the system architecture. On a 32-bit system, the size of a pointer is usually 4 bytes, while on a 64-bit system, it is typically 8 bytes. Therefore, the statement that the sizes of an integer and a pointer must be the same is false.

Explanation

In C, the sizes of an integer and a pointer are not required to be the same. The size of an integer is typically 4 bytes, while the size of a pointer can vary depending on the system architecture. On a 32-bit system, the size of a pointer is usually 4 bytes, while on a 64-bit system, it is typically 8 bytes. Therefore, the statement that the sizes of an integer and a pointer must be the same is false.

4. Predict the output

#include <stdio.h> int main() { float c = 5.0; printf ("Temperature in Fahrenheit is %.2f", (9/5)*c + 32); return 0; }

Temperature in Fahrenheit is 41.00

Temperature in Fahrenheit is 37.00

Temperature in Fahrenheit is 0.00

Compiler Error

The code is calculating the temperature in Fahrenheit using the formula (9/5)*c + 32, where c is the temperature in Celsius. In this case, c is initialized to 5.0. The expression (9/5)*c + 32 is evaluated as (1)*5.0 + 32, which results in 37.00. Therefore, the output is "Temperature in Fahrenheit is 37.00".

Explanation

The code is calculating the temperature in Fahrenheit using the formula (9/5)*c + 32, where c is the temperature in Celsius. In this case, c is initialized to 5.0. The expression (9/5)*c + 32 is evaluated as (1)*5.0 + 32, which results in 37.00. Therefore, the output is "Temperature in Fahrenheit is 37.00".

5. Output of following program?

#include<stdio.h> int main() { float x = 0.1; if ( x == 0.1 ) printf("IF"); else if (x == 0.1f) printf("ELSE IF"); else printf("ELSE"); }

ELSE IF

IF

ELSE

The output of the program is "ELSE IF". This is because the variable x is declared as a float and assigned the value 0.1. However, the if statement checks if x is equal to 0.1, which is a double precision value. Since the float value 0.1 is not exactly equal to the double value 0.1, the condition in the if statement evaluates to false. The else if statement checks if x is equal to 0.1f, which is the float value of 0.1. Since x is equal to 0.1, the condition in the else if statement evaluates to true and the corresponding printf statement is executed, resulting in the output "ELSE IF".

Explanation

The output of the program is "ELSE IF". This is because the variable x is declared as a float and assigned the value 0.1. However, the if statement checks if x is equal to 0.1, which is a double precision value. Since the float value 0.1 is not exactly equal to the double value 0.1, the condition in the if statement evaluates to false. The else if statement checks if x is equal to 0.1f, which is the float value of 0.1. Since x is equal to 0.1, the condition in the else if statement evaluates to true and the corresponding printf statement is executed, resulting in the output "ELSE IF".

6. Output?

int main() { void *vptr, v; v = 0; vptr = &v; printf("%v", *vptr); getchar(); return 0; }

0

Compiler error

Garbage value

The given code will result in a compiler error. This is because the format specifier used in the printf statement is incorrect. The correct format specifier for printing a void pointer is "%p", not "%v". Since the code is trying to print the value of a void pointer using an incorrect format specifier, it will result in a compiler error.

Explanation

The given code will result in a compiler error. This is because the format specifier used in the printf statement is incorrect. The correct format specifier for printing a void pointer is "%p", not "%v". Since the code is trying to print the value of a void pointer using an incorrect format specifier, it will result in a compiler error.

7. Assume that the size of char is 1 byte and negatives are stored in 2's complement form

#include<stdio.h> int main() { char c = 125; c = c+10; printf("%d", c); return 0; }

135

+INF

-121

-8

In this code, the variable 'c' is declared as a char with an initial value of 125. Then, 'c' is assigned a new value by adding 10 to its current value. However, since the range of a char in 2's complement form is -128 to 127, adding 10 to 125 will result in an overflow. This means that the value will wrap around to the minimum value in the range, which is -128. Therefore, the final value of 'c' is -121.

Explanation

In this code, the variable 'c' is declared as a char with an initial value of 125. Then, 'c' is assigned a new value by adding 10 to its current value. However, since the range of a char in 2's complement form is -128 to 127, adding 10 to 125 will result in an overflow. This means that the value will wrap around to the minimum value in the range, which is -128. Therefore, the final value of 'c' is -121.

8. Predict the output of following C program

#include <stdio.h> int main() { char a = '\012'; printf("%d", a); return 0; }

Compiler error

12

10

Empty

The program is using the format specifier "%d" in the printf() function to print the value of the variable 'a'. The variable 'a' is assigned the character '\012', which is an octal representation of the decimal value 10. Therefore, the output of the program will be 10.

Explanation

The program is using the format specifier "%d" in the printf() function to print the value of the variable 'a'. The variable 'a' is assigned the character '\012', which is an octal representation of the decimal value 10. Therefore, the output of the program will be 10.

9. #include <stdio.h> int main() { if (sizeof(int) > -1) printf("Yes"); else printf("No"); return 0; }

Yes

No

Compiler error

Run time error

The code checks if the size of an integer is greater than -1. Since the size of an integer is always a positive value, the condition will always be true. Therefore, "Yes" will never be printed and "No" will always be printed.

Explanation

The code checks if the size of an integer is greater than -1. Since the size of an integer is always a positive value, the condition will always be true. Therefore, "Yes" will never be printed and "No" will always be printed.