Set

Attribute

Each value in the set(no matter what type) should be unique.

Type of set

set

Elements in the set are sorted in ACSENDING order.

unordered_set

The elements in the set are NOT ordered. Save running time.

Functions

empty()

if(!set.empty()) means if the set is not empty, then go inside the if-block.

size()

set.size() will return the numbers of elements in the set.

insert()

Different from map. Map can use map[key] = value or map.insert({key, value}).

find()

Get the iterator to element. set.find(key) == set.end() means the key does not exist in the set.

count()

Count elements of the key. if set.count(key) == 0 means the key does not exist in the set.

erase(iterator position)

remove specific element

clear()

remove all the elements in the set