+ mapped_type& at(const key_type& key) {
+ iterator it = find(key);
+ if (it != end()) {
+ return it->second;
+ }
+ throw std::out_of_range("sorted_vector_map::at");
+ }
+
+ const mapped_type& at(const key_type& key) const {
+ const_iterator it = find(key);
+ if (it != end()) {
+ return it->second;
+ }
+ throw std::out_of_range("sorted_vector_map::at");
+ }
+