Precautions for containers

1. Global function: Find (Begin,end,value); Delete all elements that are value

2. Always pay attention to the extra-tails when using iterators.

3.list::remove (Elem); Delete all elements of Elem

4.int set::erase (Elem); Delete all elements of Elem

5.iterator find (Elem); Find the first elem.

6.pair<set<t>::iterator,bool result> Set::insert (elem); Result for Insert success

7. When iterating over elements, beware of the presence of iterators

8.map Insertion Method Three: C.insert (Map<t1,t2>::value_type (T1 A, T2 b));

9.map A;

A[key]=value; exists on replace, does not exist insert

10.multimap is a typical container for dictionaries