Usage of this next_combination code

Question

Currently I am trying to generate combinations from a vector that contains some integers. For now I want it to print out all of the combinations that are of length to_generate. I found this code at combination and permutation in C++ that uses std::next_permutation to generate combinations. The next_combination code is as follows:

template<class RandIt, class Compare>
bool next_combination(RandIt first, RandIt mid, RandIt last, Compare comp)
{
    std::sort(mid, last, std::tr1::bind(comp, std::tr1::placeholders::_2
                                        , std::tr1::placeholders::_1));
    return std::next_permutation(first, last, comp);
}

I tried to call it like this:

bool mycomp (int c1, int c2)
{ return (c1)<(c2); }


void test_combos(int to_generate){
    std::vector<int> combo(30);
    for(int i=0;i<30;++i){
        combo.push_back(i);
    }
    while(next_combination<std::vector<int>::iterator,   bool>(combo.begin(),combo.begin()+to_generate,combo.end(),mycomp)){
        for(std::vector<int>::iterator iter = combo.begin(); iter != combo.end() ; ++iter){
            std::cout << *iter << " ";
        }
    }
}

but I get a huge stl garbled error message. Is there anything really obvious going wrong here?

Which headers can I find std::placeholder?

As requested, here is the error message:

$ make
g++ -g -std=c++0x -I /usr/lib/ -c equity.cpp
In file included from /usr/include/c++/4.4/algorithm:62,
                 from misc.hpp:6,
                 from equity.cpp:3:
/usr/include/c++/4.4/bits/stl_algo.h: In function ‘bool std::next_permutation(_BIter, _BIter, _Compare) [with _BIter = __gnu_cxx::__normal_iterator > >, _Compare = bool]’:
misc.hpp:15:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/bits/stl_algo.h:3655: error: ‘__comp’ cannot be used as a function
/usr/include/c++/4.4/bits/stl_algo.h:3658: error: ‘__comp’ cannot be used as a function
In file included from /usr/include/c++/4.4/functional:70,
                 from /usr/include/c++/4.4/memory:70,
                 from /usr/include/boost/config/no_tr1/memory.hpp:21,
                 from /usr/include/boost/get_pointer.hpp:12,
                 from /usr/include/boost/bind/mem_fn.hpp:25,
                 from /usr/include/boost/mem_fn.hpp:22,
                 from /usr/include/boost/bind/bind.hpp:26,
                 from /usr/include/boost/bind.hpp:22,
                 from misc.hpp:4,
                 from equity.cpp:3:
/usr/include/c++/4.4/tr1_impl/functional: At global scope:
/usr/include/c++/4.4/tr1_impl/functional: In instantiation of ‘std::_Result_of_impl’:
/usr/include/c++/4.4/tr1_impl/functional:149:   instantiated from ‘std::result_of’
/usr/include/c++/4.4/bits/stl_algo.h:124:   instantiated from ‘const _Tp& std::__median(const _Tp&, const _Tp&, const _Tp&, _Compare) [with _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/tr1_impl/functional:195: error: ‘const volatile bool’ is not a class, struct, or union type
/usr/include/c++/4.4/tr1_impl/functional: In instantiation of ‘std::_Result_of_impl’:
/usr/include/c++/4.4/tr1_impl/functional:149:   instantiated from ‘std::result_of’
/usr/include/c++/4.4/bits/stl_algo.h:124:   instantiated from ‘const _Tp& std::__median(const _Tp&, const _Tp&, const _Tp&, _Compare) [with _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/tr1_impl/functional:195: error: ‘volatile bool’ is not a class, struct, or union type
/usr/include/c++/4.4/tr1_impl/functional: In instantiation of ‘std::_Result_of_impl’:
/usr/include/c++/4.4/tr1_impl/functional:149:   instantiated from ‘std::result_of’
/usr/include/c++/4.4/bits/stl_algo.h:124:   instantiated from ‘const _Tp& std::__median(const _Tp&, const _Tp&, const _Tp&, _Compare) [with _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/tr1_impl/functional:195: error: ‘const bool’ is not a class, struct, or union type
/usr/include/c++/4.4/tr1_impl/functional: In instantiation of ‘std::_Result_of_impl’:
/usr/include/c++/4.4/tr1_impl/functional:149:   instantiated from ‘std::result_of’
/usr/include/c++/4.4/bits/stl_algo.h:124:   instantiated from ‘const _Tp& std::__median(const _Tp&, const _Tp&, const _Tp&, _Compare) [with _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/tr1_impl/functional:195: error: ‘bool’ is not a class, struct, or union type
In file included from /usr/include/c++/4.4/algorithm:62,
                 from misc.hpp:6,
                 from equity.cpp:3:
/usr/include/c++/4.4/bits/stl_algo.h: In function ‘const _Tp& std::__median(const _Tp&, const _Tp&, const _Tp&, _Compare) [with _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’:
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/bits/stl_algo.h:124: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (const int&, const int&)’
/usr/include/c++/4.4/bits/stl_algo.h:125: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (const int&, const int&)’
/usr/include/c++/4.4/bits/stl_algo.h:127: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (const int&, const int&)’
/usr/include/c++/4.4/bits/stl_algo.h:131: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (const int&, const int&)’
/usr/include/c++/4.4/bits/stl_algo.h:133: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (const int&, const int&)’
In file included from /usr/include/c++/4.4/functional:70,
                 from /usr/include/c++/4.4/memory:70,
                 from /usr/include/boost/config/no_tr1/memory.hpp:21,
                 from /usr/include/boost/get_pointer.hpp:12,
                 from /usr/include/boost/bind/mem_fn.hpp:25,
                 from /usr/include/boost/mem_fn.hpp:22,
                 from /usr/include/boost/bind/bind.hpp:26,
                 from /usr/include/boost/bind.hpp:22,
                 from misc.hpp:4,
                 from equity.cpp:3:
/usr/include/c++/4.4/tr1_impl/functional: At global scope:
/usr/include/c++/4.4/tr1_impl/functional: In instantiation of ‘std::_Result_of_impl’:
/usr/include/c++/4.4/tr1_impl/functional:149:   instantiated from ‘std::result_of’
/usr/include/c++/4.4/bits/stl_algo.h:2230:   instantiated from ‘_RandomAccessIterator std::__unguarded_partition(_RandomAccessIterator, _RandomAccessIterator, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/tr1_impl/functional:195: error: ‘const volatile bool’ is not a class, struct, or union type
/usr/include/c++/4.4/tr1_impl/functional: In instantiation of ‘std::_Result_of_impl’:
/usr/include/c++/4.4/tr1_impl/functional:149:   instantiated from ‘std::result_of’
/usr/include/c++/4.4/bits/stl_algo.h:2230:   instantiated from ‘_RandomAccessIterator std::__unguarded_partition(_RandomAccessIterator, _RandomAccessIterator, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/tr1_impl/functional:195: error: ‘volatile bool’ is not a class, struct, or union type
/usr/include/c++/4.4/tr1_impl/functional: In instantiation of ‘std::_Result_of_impl’:
/usr/include/c++/4.4/tr1_impl/functional:149:   instantiated from ‘std::result_of’
/usr/include/c++/4.4/bits/stl_algo.h:2230:   instantiated from ‘_RandomAccessIterator std::__unguarded_partition(_RandomAccessIterator, _RandomAccessIterator, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/tr1_impl/functional:195: error: ‘const bool’ is not a class, struct, or union type
/usr/include/c++/4.4/tr1_impl/functional: In instantiation of ‘std::_Result_of_impl’:
/usr/include/c++/4.4/tr1_impl/functional:149:   instantiated from ‘std::result_of’
/usr/include/c++/4.4/bits/stl_algo.h:2230:   instantiated from ‘_RandomAccessIterator std::__unguarded_partition(_RandomAccessIterator, _RandomAccessIterator, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/tr1_impl/functional:195: error: ‘bool’ is not a class, struct, or union type
In file included from /usr/include/c++/4.4/algorithm:62,
                 from misc.hpp:6,
                 from equity.cpp:3:
/usr/include/c++/4.4/bits/stl_algo.h: In function ‘_RandomAccessIterator std::__unguarded_partition(_RandomAccessIterator, _RandomAccessIterator, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’:
/usr/include/c++/4.4/bits/stl_algo.h:2301:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/bits/stl_algo.h:2230: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (int&, int&)’
/usr/include/c++/4.4/bits/stl_algo.h:2233: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (int&, int&)’
/usr/include/c++/4.4/bits/stl_algo.h: In function ‘void std::__insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’:
/usr/include/c++/4.4/bits/stl_algo.h:2193:   instantiated from ‘void std::__final_insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5260:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/bits/stl_algo.h:2128: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (int&, int&)’
/usr/include/c++/4.4/bits/stl_algo.h: In function ‘void std::__heap_select(_RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’:
/usr/include/c++/4.4/bits/stl_algo.h:5108:   instantiated from ‘void std::partial_sort(_RAIter, _RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2288:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/bits/stl_algo.h:1919: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (int&, int&)’
/usr/include/c++/4.4/bits/stl_algo.h: In function ‘void std::__unguarded_linear_insert(_RandomAccessIterator, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’:
/usr/include/c++/4.4/bits/stl_algo.h:2134:   instantiated from ‘void std::__insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2193:   instantiated from ‘void std::__final_insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5260:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/bits/stl_algo.h:2084: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (int&, int&)’
In file included from /usr/include/c++/4.4/bits/stl_algo.h:62,
                 from /usr/include/c++/4.4/algorithm:62,
                 from misc.hpp:6,
                 from equity.cpp:3:
/usr/include/c++/4.4/bits/stl_heap.h: In function ‘void std::__adjust_heap(_RandomAccessIterator, _Distance, _Distance, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Distance = long int, _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’:
/usr/include/c++/4.4/bits/stl_heap.h:434:   instantiated from ‘void std::make_heap(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:1917:   instantiated from ‘void std::__heap_select(_RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5108:   instantiated from ‘void std::partial_sort(_RAIter, _RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2288:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/bits/stl_heap.h:303: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (int&, int&)’
/usr/include/c++/4.4/bits/stl_heap.h: In function ‘void std::__push_heap(_RandomAccessIterator, _Distance, _Distance, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Distance = long int, _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’:
/usr/include/c++/4.4/bits/stl_heap.h:316:   instantiated from ‘void std::__adjust_heap(_RandomAccessIterator, _Distance, _Distance, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Distance = long int, _Tp = int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_heap.h:434:   instantiated from ‘void std::make_heap(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:1917:   instantiated from ‘void std::__heap_select(_RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5108:   instantiated from ‘void std::partial_sort(_RAIter, _RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:2288:   instantiated from ‘void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = long int, _Compare = std::_Bind, std::_Placeholder)>]’
/usr/include/c++/4.4/bits/stl_algo.h:5258:   instantiated from ‘void std::sort(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator > >, _Compare = std::_Bind, std::_Placeholder)>]’
misc.hpp:13:   instantiated from ‘bool next_combination(RandIt, RandIt, RandIt, Compare) [with RandIt = __gnu_cxx::__normal_iterator > >, Compare = bool]’
equity.cpp:28:   instantiated from here
/usr/include/c++/4.4/bits/stl_heap.h:180: error: no match for call to ‘(std::_Bind, std::_Placeholder)>) (int&, int&)’
make: *** [equity.o] Error 1

Please don't be scared of "huge garbled error messages"; some of us can read them, and there are tools you can use to compact and simplify them. — Karl Knechtel, Dec 14 '10 at 06:24
It compiles if you remove the `bool` template parameter from the template instantiation in the `while` loop. Not sure that is the problem you are facing. — Naveen, Dec 14 '10 at 06:30
@Naveen, that seems to fix it, but I have no idea why this is the case. — shuttle87, Dec 15 '10 at 09:31

Pawel Zubrycki · Accepted Answer · 2010-12-15T14:13:00.470

3

The second template argument shouldn't be bool. You can allow compiller to handle types and simply write:

while(next_combination(combo.begin(), combo.begin() + to_generate, combo.end(), std::less<int>()))
    for(std::vector<int>::iterator iter = combo.begin(); iter != combo.end() ; ++iter)
        std::cout << *iter << " ";

And use spaces - it makes code look better.

edited Dec 15 '10 at 14:13

answered Dec 14 '10 at 17:02

Pawel Zubrycki

2,663
15
26

I'm fairly inexperienced with c++ templates, why does bool not work? Is the second argument not the return type of mycomp? – shuttle87 Dec 14 '10 at 17:22
1

Second argument is a type of `comp` (`mycomp` in this case), which is probably `bool (*)(int, int)` as it's pointer to function. And you can use `std::less()` instead of your own `mycomp` function. – Pawel Zubrycki Dec 14 '10 at 17:24

Usage of this next_combination code

1 Answers1

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