Binary Search as Divide and Conquer in DSA C - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to find the middle index in binary search.

DSA C

int mid = low + (high [1] low) / 2;

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

A-

B+

C*

D/

Attempts:

3 left

💡 Hint

Common Mistakes

Using multiplication instead of addition.

Dividing before subtracting.

The middle index is calculated by adding low to half the difference between high and low.

2fill in blank

medium

Complete the code to check if the middle element is the target.

DSA C

if (arr[mid] [1] target) return mid;

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

A==

B<

C>

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using assignment operator '=' instead of comparison '=='.

Using inequality operators instead of equality.

We check if the middle element equals the target to return its index.

3fill in blank

hard

Fix the error in updating the low index when target is greater than middle element.

DSA C

if (arr[mid] < target) low = [1];

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

Amid

Bmid + 1

Cmid - 1

Dlow + 1

Attempts:

3 left

💡 Hint

Common Mistakes

Setting low to mid instead of mid + 1.

Decreasing low index.

If the target is greater than the middle element, we move low to mid + 1 to search the right half.

4fill in blank

hard

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

DSA C

if (arr[mid] > target) high = [1]; else low = [2];

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

Amid - 1

Bmid + 1

Cmid

Dhigh - 1

Attempts:

3 left

💡 Hint

Common Mistakes

Using mid instead of mid - 1 or mid + 1.

Swapping low and high updates.

If target is less, high moves to mid - 1; else low moves to mid + 1.

5fill in blank

hard

Fill all three blanks to complete the binary search function.

DSA C

int binarySearch(int arr[], int low, int high, int target) {
    while (low <= high) {
        int mid = low + (high [1] low) / 2;
        if (arr[mid] == target) return [2];
        else if (arr[mid] < target) low = mid [3] 1;
        else high = mid - 1;
    }
    return -1;
}

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

A+

Bmid

C-

Dlow

Attempts:

3 left

💡 Hint

Common Mistakes

Incorrect mid calculation causing infinite loops.

Returning wrong index or updating low/high incorrectly.

The middle index is calculated by adding low to half the difference (high - low). If the middle element matches target, return mid. If target is greater, move low to mid + 1.