143 /// If an element with the key x exists in the map, then a reference to its associated value is returned. Otherwise the pair x,T() is inserted into the map and a reference to the default object T() is returned.
173 /// If a value_type with the same key as x is not present in the map, then x is inserted into the map. Otherwise, the pair is not inserted. A position may be supplied as a hint regarding where to do the insertion. If the insertion is done right after position, then it takes amortized constant time. Otherwise it takes O(log N) time.