Stack overflow detection in Embedded C - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a stack pointer variable.

Embedded C

int [1] = -1;  // Stack pointer initialized

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Astack_ptr

Btop

Csp

Dpointer

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name that is not descriptive of the stack pointer.

Initializing the pointer with a wrong value.

The variable 'top' is commonly used as the stack pointer to track the top element index.

2fill in blank

medium

Complete the code to check if the stack is full.

Embedded C

if (top == [1] - 1) {
    // Stack is full
}

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ASIZE

BMAX_SIZE

CSTACK_SIZE

DMAX_STACK

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong constant name for stack size.

Checking for equality with the wrong value.

The stack is full when the top index equals STACK_SIZE - 1, the last valid index.

3fill in blank

hard

Fix the error in the stack overflow detection condition.

Embedded C

if (top [1] STACK_SIZE) {
    // Overflow detected
}

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A>=

B==

C>

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' which misses cases where top is greater than STACK_SIZE.

Using '<=' which is incorrect for overflow detection.

The stack overflows if top is greater than or equal to STACK_SIZE, which is beyond the last valid index.

4fill in blank

hard

Fill both blanks to correctly update the stack pointer and detect overflow.

Embedded C

top [1] top + 1;
if (top [2] STACK_SIZE) {
    // Handle overflow
}

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A=

B>=

C>

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '+' instead of '=' for assignment.

Using '>' instead of '>=' for overflow check.

First, increment the top pointer with '=', then check if it is greater than or equal to STACK_SIZE to detect overflow.

5fill in blank

hard

Fill all three blanks to implement a safe push function with overflow detection.

Embedded C

void push(int stack[], int value) {
    if (top [1] STACK_SIZE - 1) {
        // Stack overflow error
        return;
    }
    top [2] top + 1;
    stack[[3]] = value;
}

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

A>=

B=

Ctop

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' instead of '>=' in overflow check.

Using '+' instead of '=' for increment.

Using wrong index for stack assignment.

Check if top is greater or equal to STACK_SIZE - 1 to detect full stack, then increment top with '=', and assign value to stack[top].