Bubble, Selection, Insertion Sort: Who is the Entry-Level 'Sorting King'?

This article introduces the significance of sorting and three basic sorting algorithms. Sorting is a fundamental operation that rearranges data according to rules to achieve a more ordered state, and it is a prerequisite for understanding complex algorithms. The core ideas and characteristics of the three algorithms are as follows: Bubble Sort repeatedly "bubbles" the largest number to the end through multiple passes, with an intuitive logic but frequent swaps, having a time complexity of O(n²). Selection Sort selects the smallest number in each round and inserts it, with fewer swaps but instability, also with O(n²) complexity. Insertion Sort is similar to arranging playing cards, suitable for small-scale or nearly ordered data, and its complexity is close to O(n). Although these three algorithms are simple, they form the foundation of more complex sorts (such as Heap Sort and Merge Sort). For beginners, it is more important to grasp the core ideas of "selecting the smallest, inserting appropriately, and bubbling the largest," and to understand the thinking of "gradually building an ordered sequence," rather than getting caught up in efficiency. This is the key to understanding the essence of sorting.