7.1 Dictionaries A dictionary is a collection of elements each element has a field called key, and no two elements have the same key value. Operations: Insert(x): insert an element with a specified key value Search(k,x): search an element with a specified key
5.1 definition of stack Definition A stack is a linear list in which insertions and deletions take place at the same end. This end is called the top. The other end of the list is called the bottom. It is also called a LIFO(last-in-first-out) list