artem-ogre / combinations_cpp Goto Github PK

In the method size() I think there is a bug. I was not able to compile any code using size().

I believe that the size of the vector needs to be referenced somewhere there instead of directly using std::multiplies.

To reproduce:

#include "combinations.hpp"
#include <iostream>
int main()
{
    std::vector<std::vector<double> > x(4, std::vector<double>(4, 42.0));
    auto ft = make_combinations(x);
    std::cout << ft.size() << std::endl;
    return 0;
}

Expected output: 256

Compilation error:

/usr/include/c++/5/bits/stl_numeric.h: In instantiation of ‘_Tp std::accumulate(_InputIterator, _InputIterator, _Tp, _BinaryOperation) [with _InputIterator = __gnu_cxx::__normal_iterator<const std::vector, std::vector<std::vector > >; _Tp = int; _BinaryOperation = std::multiplies]’:
combinations.hpp:177:52: required from ‘combinations::size_type combinations::size() const [with SetsIter = __gnu_cxx::__normal_iterator<const std::vector, std::vector<std::vector > >; combinations::size_type = long unsigned int]’
text.cpp:14:26: required from here
/usr/include/c++/5/bits/stl_numeric.h:154:22: error: no match for call to ‘(std::multiplies) (int&, const std::vector&)’
__init = __binary_op(__init, *__first);
^
In file included from /usr/include/c++/5/string:48:0,
from /usr/include/c++/5/bits/locale_classes.h:40,
from /usr/include/c++/5/bits/ios_base.h:41,
from /usr/include/c++/5/ios:42,
from /usr/include/c++/5/ostream:38,
from /usr/include/c++/5/iterator:64,
from combinations.hpp:25,
from text.cpp:1:
/usr/include/c++/5/bits/stl_function.h:191:7: note: candidate: _Tp std::multiplies<_Tp>::operator()(const _Tp&, const _Tp&) const [with _Tp = long unsigned int]
operator()(const _Tp& __x, const _Tp& __y) const
^
/usr/include/c++/5/bits/stl_function.h:191:7: note: no known conversion for argument 2 from ‘const std::vector’ to ‘const long unsigned int&’