Part III Data Structures

1. 不同集合存在的原因是為了因應不同的操作需求, 例如 dictionary 主要用來做 insertion, deletion, test for existance
   heap data structure, min-priocity queue: insertion and extracting the smallest element from a set

2. Operations on dynamic sets could be grouped into two categories: queries and modifying operations

   1. SEARCH(S, x)
   2. INSERT(S, x)
   3. DELETE(S, x)
   4. MINIMUM(S)
   5. MAXIMUM(S)
   6. SUCCESSOR(S, x)
   7. PREDECESSOR(S, x)