Why dynamic memory is risky in embedded in Embedded C - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a pointer for dynamic memory allocation.

Embedded C

int* [1];

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Aptr

Bint

Carray

Dmalloc

Attempts:

3 left

💡 Hint

Common Mistakes

Using a type name instead of a variable name.

The pointer ptr is used to hold the address of dynamically allocated memory.

2fill in blank

medium

Complete the code to allocate memory dynamically for 10 integers.

Embedded C

ptr = (int*) [1](10 * sizeof(int));

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Afree

Bmalloc

Csizeof

Dcalloc

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'free' instead of 'malloc'.

malloc allocates a block of memory of the given size.

3fill in blank

hard

Fix the error in the code to properly free the allocated memory.

Embedded C

if (ptr != NULL) {
    [1](ptr);
}

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Amalloc

Bcalloc

Cfree

Drealloc

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'malloc' or 'calloc' instead of 'free'.

free releases the memory previously allocated by malloc.

4fill in blank

hard

Fill both blanks to check if memory allocation failed and handle it.

Embedded C

ptr = (int*) malloc(sizeof(int) * 5);
if (ptr [1] NULL) {
    [2]("Allocation failed!\n");
}

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A==

Bprintf

C!=

Dscanf

Attempts:

3 left

💡 Hint

Common Mistakes

Using '!=' instead of '==' in the condition.

Using 'scanf' instead of 'printf'.

We check if ptr is equal to NULL to detect failure, then print a message.

5fill in blank

hard

Fill all three blanks to check if memory allocation failed, print an error if it did, and initialize the array otherwise.

Embedded C

int* ptr = (int*) malloc(sizeof(int) * 10);
if (ptr [1] NULL) {
    [2]("Memory allocation failed!\n");
} else {
    for (int i = 0; i [3] 10; i++) {
        ptr[i] = i * i;
    }
}

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A==

Bprintf

C<

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '!=' instead of '==' for failure check.

Using '>' instead of '<' in loop condition.

We check if ptr == NULL to detect allocation failure, print an error if failed, and loop to fill ptr[i] = i * i for i < 10 if successful.