Binary Search Iterative Approach in DSA Javascript - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to initialize the middle index in the binary search loop.

DSA Javascript

let mid = Math.floor(([1] + high) / 2);

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

A0

Bmid

Chigh

Dlow

Attempts:

3 left

💡 Hint

Common Mistakes

Using mid instead of low causes incorrect calculation.

Using high alone does not consider the lower bound.

The middle index is calculated by averaging the low and high indices. Here, low is the correct variable to use.

2fill in blank

medium

Complete the code to update the low index when the target is greater than the middle element.

DSA Javascript

if (arr[mid] < target) {
  [1] = mid + 1;
}

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

Amid

Blow

Chigh

Dtarget

Attempts:

3 left

💡 Hint

Common Mistakes

Updating high instead of low.

Setting low to mid instead of mid + 1.

If the target is greater than the middle element, we move the low index to one position after mid.

3fill in blank

hard

Fix the error in the loop condition to correctly run the binary search.

DSA Javascript

while ([1] <= high) {
  let mid = Math.floor((low + high) / 2);
  // rest of code
}

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

Atarget

Bmid

Clow

Dhigh

Attempts:

3 left

💡 Hint

Common Mistakes

Using mid in the condition causes infinite loops.

Using target in the condition is invalid.

The loop should continue while low is less than or equal to high. Using mid or others is incorrect.

4fill in blank

hard

Fill both blanks to correctly update the high index when the target is less than the middle element.

DSA Javascript

if (arr[mid] > target) {
  [1] = mid [2] 1;
}

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

Ahigh

Blow

C-

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Updating low instead of high.

Adding 1 instead of subtracting 1.

When the target is less than the middle element, we move the high index to one less than mid.

5fill in blank

hard

Fill both blanks to return the index if the target is found, or -1 if not found.

DSA Javascript

if (arr[mid] === target) {
  return [1];
}

// After loop
return [2];

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

Amid

B-1

Clow

Dhigh

Attempts:

3 left

💡 Hint

Common Mistakes

Returning low or high instead of mid.

Returning 0 instead of -1 when not found.

Return mid when target is found. Return -1 if not found after loop ends.