Why preprocessor is used - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to include a header file using the preprocessor directive.

C

#include [1]stdio.h[2]

Drag options to blanks, or click blank then click option'

A<>

B[]

C{}

D""

Attempts:

3 left

💡 Hint

Common Mistakes

Using double quotes instead of angle brackets for standard headers.

Forgetting the #include directive.

The preprocessor directive #include <stdio.h> tells the compiler to include the standard input-output header file.

2fill in blank

medium

Complete the code to define a constant using the preprocessor.

C

#define [1] 100

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Aprintf

Bint

Cmain

DMAX_SIZE

Attempts:

3 left

💡 Hint

Common Mistakes

Using keywords like int or main as constant names.

Not using uppercase for constants.

The #define directive creates a constant named MAX_SIZE with value 100.

3fill in blank

hard

Fix the error in the conditional compilation directive.

C

#if [1]
    printf("Debug mode\n");
#endif

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ADEBUG = 1

Bdefined(DEBUG)

CDEBUG == 1

DDEBUG > 0

Attempts:

3 left

💡 Hint

Common Mistakes

Using assignment (=) instead of comparison (==).

Not using defined() to check macro existence.

The #if defined(DEBUG) checks if DEBUG is defined for conditional compilation.

4fill in blank

hard

Fill both blanks to create a macro that calculates the square of a number.

C

#define SQUARE([1]) ([2] * [2])

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Ax

By

Cz

Dnum

Attempts:

3 left

💡 Hint

Common Mistakes

Using different names for the parameter in the macro body.

Forgetting parentheses around the expression.

The macro uses x as the parameter and calculates (x * x) to find the square.

5fill in blank

hard

Fill all three blanks to create a macro that returns the maximum of two values.

C

#define MAX([1], [2]) (([3]) > ([2]) ? ([3]) : ([2]))

Drag options to blanks, or click blank then click option'

Aa

Bb

Cx

Dy

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing parameter names in the macro body.

Not using parentheses properly.

The macro uses parameters a and b and compares a with b to return the maximum.