#include<fstream>
#include<iostream>
#include<algorithm>
#include<iterator>
#include<string>
#include<vector>
 
using namespace std;
 
 
 
int main()
{
 string from, to;
 cin >> from >> to;
 
 ifstream is(from.c_str());
 istream_iterator<string> ii(is);
 istream_iterator<string> eos;
 
 vector<string> b(ii,eos);
 sort(b.begin(),b.end());
 
 ofstream os(to.c_str());
 ostream_iterator<string> oo(os,"\n" );
 
 unique_copy(b.begin(),b.end(),oo);
 return !is.eof() || !os;
}

--------------------Configuration: fichier - Win32 Debug--------------------
Compiling...
feuil01.cpp
C:\Program Files\Microsoft Visual Studio\MyProjects\fichier\feuil01.cpp(22) : error C2664: '__thiscall std::vector<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::allocator<class std::basic_string<c
har,struct std::char_traits<char>,class std::allocator<char> > > >::std::vector<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::allocator<class std::basic_string<char,struct std::char_traits<char>,c
lass std::allocator<char> > > >(unsigned int,const class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > &,const class std::allocator<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<c
har> > > & )' : cannot convert parameter 1 from 'class std::istream_iterator<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,char,struct std::char_traits<char> >' to 'unsigned int'
        No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called
Error executing cl.exe.
 
fichier.exe - 1 error(s), 0 warning(s)