Jumping into C++

for ( vector ::iterator itr = vec.begin(), end = vec.end(); itr != end; ++itr )

vector ::iterator

itr++;

vector a_vector( 10 );

map—taking one value and using it to look up another.

a_vector[ i ] = 0;

a_vector.size();

The iterator, when you dereference it, has two fields, first and second. The first field is the key, and the second field is the value.

name_to_address.clear();