Sort as Preprocessing

Find Duplicates In a sorted array, duplicates are always adjacent. One pass finds them all. Merge Intervals A classic problem: merge overlapping intervals. Sorting by start time makes overlaps easy to detect. K Closest Points The algorithms covered in this lesson all follow the same principle: choose a data structure or preprocessing step that reduces the number of comparisons you need to make at each stage. Advanced problem-solving strategies prepare you for the kind of complex, multi-step challenges found in real-world software development. Put your skills to the test with hands-on challenges in the Python Builder.