Lesson overview · Free interview practice

K-way Merge

Merge multiple sorted arrays.

Topics in the full lesson
  • Concept and Use Cases
  • When to Use
  • Time and Space Complexity
  • Merging K Sorted Arrays
  • Merging K Sorted Linked Lists

Practice Problems

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CodingMedium

Find K Pairs with Smallest Sums

Question

Given two integer arrays nums1 and nums2 sorted in non-decreasing order and an integer k, return the k pairs (u, v) (with u from nums1 and v from nums2) that have the smallest sums.

Take a moment to think about this before revealing the answer

Explain your reasoning or try an implementation before comparing answers.

Practice on LeetCode
CodingHard

Smallest Range Covering Elements from K Lists

Question

You are given k sorted integer lists. Find the smallest range [a, b] that includes at least one number from each of the k lists. Range [a, b] is smaller than [c, d] if b - a < d - c, or if b - a == d - c and a < c.

Take a moment to think about this before revealing the answer

Explain your reasoning or try an implementation before comparing answers.

Practice on LeetCode
CodingHard

Merge k Sorted Lists

Question

Combine multiple sorted lists into a single sorted list, efficiently merging and ordering elements from each input list in O(n log k) time complexity.

Take a moment to think about this before revealing the answer

Explain your reasoning or try an implementation before comparing answers.

Practice on LeetCode

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