Sorting & Searching

Master fundamental sorting and searching algorithms and their applications.

Showing 6 of 6 questions
Easy: 0 Medium: 0 Hard: 0
QUESTIONDIFFICULTY
Binary Search
Find the index of a target value in a sorted array
Easy
Sum of Mutated Array Closest to Target
Find a value to replace elements larger than it so the array sum is closest to target
Medium
Search in Rotated Sorted Array
Find a target in a rotated sorted array in O(log n) time
Medium
Kth Largest Element
Find the kth largest element in an unsorted array
Medium
Merge Intervals
Merge all overlapping intervals in an array
Medium
Median of Two Sorted Arrays
Find the median of two sorted arrays in O(log(min(m,n))) time
Hard

Overview

Sorting and searching are fundamental algorithmic techniques. This section covers classic algorithms and their practical applications in interview problems.

Key Concepts

  • Binary search and variants
  • Quick sort and merge sort
  • Counting sort and radix sort
  • Search in rotated arrays
  • Finding kth element
  • Custom comparators

Common Problems

Easy

  • Binary Search
  • Search Insert Position
  • First Bad Version
  • Sqrt(x)

Medium

  • Search in Rotated Sorted Array
  • Find Peak Element
  • Kth Largest Element
  • Merge Intervals

Hard

  • Median of Two Sorted Arrays
  • Count of Smaller Numbers After Self
  • Maximum Gap

Practice Tips

  1. Binary search template: Master the basic template
  2. Sorted input: Look for opportunities to use binary search
  3. Time complexity: Know when O(n log n) is acceptable
  4. Stability: Understand when sort stability matters

Resources