•The Insert operation attempts to
insert a key (and element) into the map. If the key is already in the map,
then Insert raises C_E; otherwise, it inserts the new
key/element pair in the map.
•Include (a variation of Insert)
attempts to insert the key, but if the key is already in
the map, it replaces the existing key/element pair with the new
key/element pair, instead of raising C_E.