#include <iostream>
#include <boost/range/algorithm.hpp>
#include <vector>

int main() 
{ 
    std::vector<int> vec = {1, 5, 3, 2, 1};
    boost::copy(boost::unique(boost::sort(vec)),
            std::ostream_iterator<int>(std::cout, ", "));
    
    return 0;
}

#include <iostream>
#include <vector>
#include <algorithm>
#include <type_traits>
#include <iterator>

#include <boost/range/algorithm.hpp>


#define RANGE(func, vec, ...) tmp_func(vec, [&]() { return func(vec.begin(), vec.end(), ##__VA_ARGS__); } )

template<typename T_vec, typename T_func>
auto tmp_func(T_vec &vec, T_func const& func) -> typename std::enable_if< std::is_void<decltype(func())>::value, T_vec& >::type 
{ func(); return vec; }

template<typename T_vec, typename T_func>
auto tmp_func(T_vec &vec, T_func const& func) -> typename std::enable_if< std::is_same<decltype(func()), decltype(vec.begin())>::value, T_vec& >::type 
{ auto it = func(); vec.resize(it - vec.begin()); return vec; }

template<typename T_vec, typename T_func>
auto tmp_func(T_vec &vec, T_func const& func) -> typename std::enable_if< !std::is_void<decltype(func())>::value && !std::is_same<decltype(func()), decltype(vec.begin())>::value, T_vec& >::type 
{ func(); return vec; }


int main() 
{ 
    std::vector<int> vec2 = {1, 5, 3, 2, 1, 1};    
    //boost::copy(boost::unique(boost::sort(vec)), std::ostream_iterator<int>(std::cout, ", "));
    RANGE(std::copy, RANGE(std::unique, RANGE(std::sort, vec2) ), std::ostream_iterator<int>(std::cout, ", "));

    return 0;
}

#include <iostream>
#include <boost/range/algorithm.hpp>
#include <vector>

int main() 
{ 
    std::vector<int> vec = {1, 5, 3, 2, 1};
    boost::copy(boost::unique(boost::sort(vec)),
            std::ostream_iterator<int>(std::cout, ", "));
    
    return 0;
}

    
    std::vector<int> vec = {1, 5, 3, 2, 1};
    std::sort(vec.begin(), vec.end());
    auto unique_end = std::unique(vec.begin(), vec.end());
    std::copy(vec.begin(), unique_end,
            std::ostream_iterator<int>(std::cout, ", "));