What's this thing doing? It's walking along the list looking for the smallest thing in the back end of the list, keeping track of where it came from and swapping it with that spot in the list. All right?

这是在做什么？是在遍历列表,找列表后端最小的元素,跟踪它从哪里来的,然后同当前点的元素交换，明白了么？

麻省理工公开课 - 计算机科学及编程导论课程节选