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/* The following code example is taken from the book
* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <iostream>
#include <string>
#include <deque>
#include <set>
#include <algorithm>
using namespace std;
/* class Person
*/
class Person {
private:
string fn; // first name
string ln; // last name
public:
Person() {
}
Person(const string& f, const string& n)
: fn(f), ln(n) {
}
string firstname() const;
string lastname() const;
// ...
};
inline string Person::firstname() const {
return fn;
}
inline string Person::lastname() const {
return ln;
}
ostream& operator<< (ostream& s, const Person& p)
{
s << "[" << p.firstname() << " " << p.lastname() << "]";
return s;
}
/* binary function predicate:
* - returns whether a person is less than another person
*/
bool personSortCriterion (const Person& p1, const Person& p2)
{
/* a person is less than another person
* - if the last name is less
* - if the last name is equal and the first name is less
*/
return p1.lastname()<p2.lastname() ||
(p1.lastname()==p2.lastname() &&
p1.firstname()<p2.firstname());
}
int main()
{
// create some persons
Person p1("nicolai","josuttis");
Person p2("ulli","josuttis");
Person p3("anica","josuttis");
Person p4("lucas","josuttis");
Person p5("lucas","otto");
Person p6("lucas","arm");
Person p7("anica","holle");
// insert person into collection coll
deque<Person> coll;
coll.push_back(p1);
coll.push_back(p2);
coll.push_back(p3);
coll.push_back(p4);
coll.push_back(p5);
coll.push_back(p6);
coll.push_back(p7);
// print elements
cout << "deque before sort():" << endl;
deque<Person>::iterator pos;
for (pos = coll.begin(); pos != coll.end(); ++pos) {
cout << *pos << endl;
}
// sort elements
sort(coll.begin(),coll.end(), // range
personSortCriterion); // sort criterion
// print elements
cout << "deque after sort():" << endl;
for (pos = coll.begin(); pos != coll.end(); ++pos) {
cout << *pos << endl;
}
}
/*
deque before sort():
[nicolai josuttis]
[ulli josuttis]
[anica josuttis]
[lucas josuttis]
[lucas otto]
[lucas arm]
[anica holle]
deque after sort():
[lucas arm]
[anica holle]
[anica josuttis]
[lucas josuttis]
[nicolai josuttis]
[ulli josuttis]
[lucas otto]
*/
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