map<string, int> myMap;
myMap["one"] = 1;
myMap["two"] = 2;
myMap["three"] = 3;

map<string, int>::iterator it = myMap.find("two");

myMap.erase( it, myMap.end() );

myMap.erase( myMap.end() );

myMap.erase( myMap.end(), myMap.end() );

if ( it != myMap.end() )
    myMap.erase( it );

map<int,int> m;
for (int i = 0; i < 5; ++i)
   m[i] = i;
m.erase( m.find(1), m.find(4) );

for (int i = 1; i <= 4; ++i )
   m.erase( m.find(i) );

a.erase( q1, q2)

a.erase(q)