Dynamic Stack Using Resizable Array in DSA Python - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add an element to the top of the stack.

DSA Python

def push(self, item):
    if self.size == len(self.array):
        self.resize()
    self.array[self.size] = [1]
    self.size += 1

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

Aitem

Bself.size

Clen(self.array)

Dself.array

Attempts:

3 left

💡 Hint

Common Mistakes

Using self.size instead of item to assign the value.

Trying to assign to self.array instead of an index.

The push method adds the given item to the top of the stack at index self.size.

2fill in blank

medium

Complete the code to remove and return the top element from the stack.

DSA Python

def pop(self):
    if self.size == 0:
        raise IndexError('pop from empty stack')
    self.size -= 1
    item = self.array[[1]]
    return item

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

A0

Bself.size

Clen(self.array) - 1

Dself.size - 1

Attempts:

3 left

💡 Hint

Common Mistakes

Accessing self.array[self.size - 1] which is incorrect after decrement.

Returning the wrong element index.

After decreasing self.size, the top element is at index self.size.

3fill in blank

hard

Fix the error in the resize method to double the array size correctly.

DSA Python

def resize(self):
    new_capacity = len(self.array) [1] 2
    new_array = [None] * new_capacity
    for i in range(self.size):
        new_array[i] = self.array[i]
    self.array = new_array

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

A//

B+

C-

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Using addition instead of multiplication.

Using integer division which reduces size.

To double the size, multiply the current length by 2.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps each word to its length if length is greater than 3.

DSA Python

{word: [1] for word in words if len(word) [2] 3}

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Alen(word)

B>

C<

Dword

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong comparison operator.

Mapping to the word itself instead of its length.

The dictionary maps each word to its length using len(word) only if the length is greater than 3.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps uppercase keys to values only if values are positive.

DSA Python

result = { [1]: [2] for k, [2] in data.items() if [2] [3] 0 }

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

Ak.upper()

Bv

C>

Dk

Attempts:

3 left

💡 Hint

Common Mistakes

Using the original key instead of uppercase.

Using wrong comparison operator or variable names.

The comprehension maps uppercase keys (k.upper()) to their values (v) only if the value is greater than zero.