Heap Concept Structure and Properties in DSA Typescript - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create an empty heap array.

DSA Typescript

const heap: number[] = [1];

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

Anull

B{}

C[]

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using {} which is an object, not an array.

Using null or 0 which are not arrays.

An empty heap is represented by an empty array [].

2fill in blank

medium

Complete the code to get the index of the left child of a node at index i.

DSA Typescript

function leftChild(i: number): number {
  return [1];
}

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A2 * i

B2 * i + 1

Ci + 1

D2 * i - 1

Attempts:

3 left

💡 Hint

Common Mistakes

Using 2 * i which is the index of the right child.

Using i + 1 which is just the next element.

In a heap stored as an array, left child index = 2 * i + 1.

3fill in blank

hard

Fix the error in the code to get the parent index of a node at index i.

DSA Typescript

function parent(i: number): number {
  return Math.floor([1]);
}

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A(i - 1) / 2

Bi / 2

C(i + 1) / 2

Di - 1

Attempts:

3 left

💡 Hint

Common Mistakes

Using i / 2 which is incorrect for zero-based arrays.

Using i - 1 which is just the previous element.

Parent index = floor((i - 1) / 2) in a heap array.

4fill in blank

hard

Fill both blanks to check if a node at index i has a left child within heap size.

DSA Typescript

function hasLeftChild(i: number, size: number): boolean {
  return [1] < [2];
}

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A2 * i + 1

B2 * i

Csize

Di

Attempts:

3 left

💡 Hint

Common Mistakes

Using 2 * i instead of 2 * i + 1 for left child.

Comparing with i instead of size.

Left child index is 2 * i + 1 and must be less than heap size.

5fill in blank

hard

Fill all three blanks to swap elements at indices i and j in the heap array.

DSA Typescript

function swap(heap: number[], i: number, j: number): void {
  const temp = heap[[1]];
  heap[[2]] = heap[[3]];
  heap[[3]] = temp;
}

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

Ai

Bj

Dtemp

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing indices i and j in assignments.

Using temp as an index instead of a value.

Swap uses temp to hold heap[i], then assigns heap[j] to heap[i], and temp back to heap[j].