Demonstrating the STL list unique functions
#include <iostream>
#include <cassert>
#include <string>
#include <list>
using namespace std;
int main()
{
string s("Stroustrup");
list<char> list1(s.begin(), s.end());
list1.sort();
list1.unique();
list<char>::iterator i;
for (i = list1.begin(); i != list1.end(); ++i)
cout << *i;
return 0;
}
Soprstu"
Remove duplicates
/* 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 <list>
#include <algorithm>
#include <iterator>
using namespace std;
void printLists (const list<int>& l1, const list<int>& l2)
{
cout << "list1: ";
copy (l1.begin(), l1.end(), ostream_iterator<int>(cout," "));
cout << endl << "list2: ";
copy (l2.begin(), l2.end(), ostream_iterator<int>(cout," "));
cout << endl << endl;
}
int main()
{
// create two empty lists
list<int> list1, list2;
// fill both lists with elements
for (int i=0; i<6; ++i) {
list1.push_back(i);
list2.push_front(i);
}
printLists(list1, list2);
// sort second list, assign to list1 and remove duplicates
list2.sort();
list1 = list2;
list2.unique();
printLists(list1, list2);
}
list1: 0 1 2 3 4 5
list2: 5 4 3 2 1 0
list1: 0 1 2 3 4 5
list2: 0 1 2 3 4 5
Remove duplicates from list with unique()
#include <iostream>
#include <list>
using namespace std;
void show(const char *msg, list<char> lst);
int main() {
list<char> lstA;
lstA.push_back("A");
lstA.push_back("F");
lstA.push_back("B");
lstA.push_back("A");
lstA.sort();
// Remove duplicates from lstA.
lstA.unique();
show("lstA after call to unique(): ", lstA);
return 0;
}
void show(const char *msg, list<char> lst) {
list<char>::iterator itr;
cout << msg << endl;
for(itr = lst.begin(); itr != lst.end(); ++itr)
cout << *itr << endl;
}