## Insert-Type Methods

Method | Description | Complexity Guarantee | Exception Guarantee
    inline std::pair<find_iterator, bool>
      insert
      (const_mapped_reference r_value)
| Inserts `r_value` into the table. Writes only if an entry with an equivalent key does not exist. If the entry was written, returns
    std::make_pair(it, true)
where `it` corresponds to the new entry; Otherwise, returns
    std::make_pair(find_end(), false)
. | O(1) average O(m) worst (m = #entries) [1] | 1,2

[1] Note that for multimap types, the mapped data part is a collection, and so the average and worst case complexities need to be multiplied by the corresponding complexities of copying collections.