Lesson overview · Free interview practice

Binary Search

Efficiently search sorted arrays.

Topics in the full lesson
  • Concept and Use Cases
  • When to Use
  • Time and Space Complexity
  • Common Problems
  • Conventional Binary Search
  • Finding the First and Last Occurrence of an Element
  • Searching in a Rotated Sorted Array
  • Finding the Peak Element in an Array

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CodingMedium

Find Minimum in Rotated Sorted Array

Question

Given a sorted array that has been rotated an unknown number of times, find the minimum element in the array.

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Explain your reasoning or try an implementation before comparing answers.

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CodingMedium

Find Peak Element

Question

A peak element is an element strictly greater than both its neighbors. Given a 0-indexed integer array nums with no two adjacent equal values, return the index of any peak element. You may assume nums[-1] = nums[n] = -∞. Solve in O(log n) time using binary search.

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Explain your reasoning or try an implementation before comparing answers.

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CodingHard

Split Array Largest Sum

Question

Given an integer array nums and an integer k, split nums into k non-empty contiguous subarrays so that the largest subarray sum is as small as possible. Return that minimized largest sum.

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Explain your reasoning or try an implementation before comparing answers.

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