Insertion Sort Algorithm in DSA Javascript - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to start the outer loop from the second element in the array.

DSA Javascript

for(let i = [1]; i < arr.length; i++) {
  // sorting logic
}

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

A1

B2

Carr.length - 1

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Starting from index 0 causes unnecessary comparisons.

Starting from the last element misses sorting the array.

The insertion sort starts from the second element (index 1) because the first element is considered sorted.

2fill in blank

medium

Complete the code to store the current element to be inserted in a variable.

DSA Javascript

let key = arr[[1]];

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Aarr.length - 1

Bi - 1

C0

Di

Attempts:

3 left

💡 Hint

Common Mistakes

Using i - 1 gets the previous element, not the current one.

Using 0 or arr.length - 1 does not refer to the current element.

The variable key holds the element at index i which we want to insert into the sorted part.

3fill in blank

hard

Fix the error in the while loop condition to correctly compare elements for insertion.

DSA Javascript

while(j >= 0 && arr[j] [1] key) {
  arr[j + 1] = arr[j];
  j--;
}

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

A<

B==

C>

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' reverses the logic and breaks sorting.

Using '==' or '<=' does not correctly shift elements.

The condition arr[j] > key checks if the current element is greater than the key to shift it right.

4fill in blank

hard

Fill both blanks to correctly shift elements right.

DSA Javascript

arr[j [1] 1] = arr[j];
j = j [2] 1;

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A+

B-

C*

D/

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-' instead of '+' for the array index causes overwriting.

Incrementing j instead of decrementing causes infinite loop.

We shift elements right by assigning to arr[j + 1] and move j left by decrementing it with j - 1.

5fill in blank

hard

Fill all three blanks to complete the insertion of the key after shifting elements.

DSA Javascript

arr[j [1] 1] = [2];

for(let i = [3]; i < arr.length; i++) {
  // insertion sort logic
}

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

A+

Bkey

C1

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-' instead of '+' causes wrong insertion position.

Using wrong variable instead of key overwrites data.

Starting loop at 0 causes unnecessary comparisons.

After shifting, we place the key at arr[j + 1]. The outer loop starts from index 1 because the first element is considered sorted.