Merge Overlapping Intervals in DSA C - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to sort intervals by their start time.

DSA C

int compare(const void *a, const void *b) {
    int *interval1 = (int *)a;
    int *interval2 = (int *)b;
    return interval1[[1]] - interval2[0];
}

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

A1

B-1

C2

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using the end time (index 1) instead of start time.

Using an invalid index like 2 or -1.

We compare intervals by their start time, which is at index 0.

2fill in blank

medium

Complete the code to check if two intervals overlap.

DSA C

if (intervals[i][0] <= merged[mergedIndex][[1]]) {
    // Overlap detected
}

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

A2

B0

C1

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Comparing start with start instead of end.

Using wrong indices.

We check if the current interval's start is less or equal to the last merged interval's end (index 1).

3fill in blank

hard

Fix the error in updating the end time of the merged interval.

DSA C

merged[mergedIndex][1] = (intervals[i][1] > merged[mergedIndex][[1]]) ? intervals[i][1] : merged[mergedIndex][1];

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

A-1

B1

C2

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using start time index 0 instead of end time index 1.

Using invalid indices.

We compare the current interval's end (index 1) with the merged interval's end (index 1).

4fill in blank

hard

Fill both blanks to correctly copy the current interval to merged when no overlap.

DSA C

mergedIndex++;
merged[mergedIndex][[1]] = intervals[i][[2]];

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A0

B1

Ci

DmergedIndex

Attempts:

3 left

💡 Hint

Common Mistakes

Using end time index 1 instead of start time 0.

Mixing up indices for source and destination.

We copy the start time (index 0) from intervals[i] to merged[mergedIndex].

5fill in blank

hard

Fill all three blanks to copy both start and end times when no overlap.

DSA C

merged[mergedIndex][[1]] = intervals[i][[2]];
merged[mergedIndex][[3]] = intervals[i][1];

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

A0

B1

CmergedIndex

Di

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing start and end indices.

Using wrong indices for merged or intervals.

Copy the start time (index 0) from intervals[i][0] to merged[mergedIndex][0] for blanks 1 and 2, and end time (index 1) for blank 3.