What Are Counting Sort and Radix Sort?

TL;DR

Counting sort is a linear-time algorithm that organizes integers by counting occurrences, while radix sort sorts numbers based on their digit positions. Both algorithms are efficient for sorting integers, especially when the range of numbers is known.

Transcript

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Key Insights

• 🧡 Counting sort and radix sort are linear-time sorting algorithms for integers within a certain range.
• 😒 Counting sort uses counting the occurrences of each integer to achieve linear time complexity.
• ⚾ Radix sort sorts the integers based on their digits, using counting sort for each digit.

Questions & Answers

Q: How does counting sort work?

Counting sort involves counting the occurrences of each integer and then outputting them in order. It uses an array of counters for each possible value of the integers.

Q: What is the time complexity of counting sort?

The time complexity of counting sort is O(n + k), where n is the number of integers and k is the maximum possible integer value.

Q: How does radix sort work?

Radix sort involves sorting the integers based on their least significant digit, then their next least significant digit, and so on. It uses counting sort as a subroutine for each digit.

Q: What is the time complexity of radix sort?

The time complexity of radix sort is O(n * c), where n is the number of integers and c is the number of digits in the largest integer.

Summary & Key Takeaways

• Counting sort: Count the occurrences of each integer and then output them in order.

• Radix sort: Sort the integers based on their least significant digit, then their next least significant digit, and so on.