Iterator

Why Use Iterators

Common Functions

begin

set<int>::iterator iter = mySet.begin();

*

++

Prefix and postfix are both OK. Same as the primitive value, same as the pointer, etc.

end

Usage

Why it Powerful

Map Iterator

Pair

Further Usage

• find
• lower_bound: returns an iterator to the first element not less than the given key
• upper_bound: returns an iterator to the first element greater than the given key
• range based for loop

Iterator Type

But some can’t, e.g. list.

• input
• output
• forward
• Bidirectional
• Random

Invalidate

All STL can be erased in this way.

Stream Iterator