Read words from standard input, sort and print out without duplicates : istream iterator « STL Algorithms Iterator « C++ Tutorial

1. C++ Tutorial
2. STL Algorithms Iterator
3. istream iterator

/* 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 <vector>
#include <string>
#include <algorithm>
#include <iterator>
using namespace std;

int main()
{
    vector<string> coll;

    /* read all words from the standard input
     * - source: all strings until end-of-file (or error)
     * - destination: coll (inserting)
     */
    copy (istream_iterator<string>(cin),    // start of source
          istream_iterator<string>(),       // end of source
          back_inserter(coll));             // destination

    // sort elements
    sort (coll.begin(), coll.end());

    /* print all elements without duplicates
     * - source: coll
     * - destination: standard output (with newline between elements)
     */
    unique_copy (coll.begin(), coll.end(),             // source
                 ostream_iterator<string>(cout,"\n")); // destination
}

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