// Program to demonstrate sorting and searching of personnel records, // showing how to define a function object that tells how to compare two // such records. #include <mstring.h> #include <vector.h> #include <algo.h> struct person { string first_name; string last_name; int number; }; void output(const person& record) { cout << record.first_name << " " << record.last_name << ", Record No. " << record.number << "\n"; } int rec_no = 1; // shouldn't really be a global variable void read_names(vector<person>& roster) { person person1; while (true) { cin >> person1.first_name; if (person1.first_name == string("---")) break; cin >> person1.last_name; person1.number = rec_no++; roster.push_back(person1); // put person1 at end of roster } } // Following is a function object type, // defines how to compare persons (for sorting/searching) struct NameCompare { bool operator()(const person& a, const person& b) { return a.last_name < b.last_name; // based on last names only } }; NameCompare nameComp; /* declare a comparison function object, to pass to sort and search algorithms */ int main() { vector<person> roster; read_names(roster); sort(roster.begin(), roster.end(), nameComp); cout << "Current persons, listed alphabetically by last name:\n\n"; for (vector<person>::iterator i = roster.begin(); i != roster.end(); ++i) output(*i); cout << "\n\n"; person search_record; while (true) { cin >> search_record.last_name; if (search_record.last_name == string("---")) break; cout << "Searching for a person named " << search_record.last_name << "...\n"; i = lower_bound(roster.begin(), roster.end(), search_record, nameComp); if ((*i).last_name == search_record.last_name) { cout << "Found "; output(*i); cout << "\n"; } else cout << "Sorry, there's no record of a person named " << search_record.last_name << "\n\n"; } return 0; }