fix "RecursiveCdoEngine::loss_unit_" init

before getting "std::min_element(lgds.begin(), lgds.end())"
in "lgds" removed all "0" elements. But this is not correct removing.
std::remove() only moving all the elements that not equal to "0" and return iterator to the new end.
instead of "0" lgds contains trash. There are two ways:
1. get iterator to the new end: std::min_element(lgds.begin(), new_end_iterator)
2. really erase all "0" from lgds: lgds.erase(std::remove(lgds.begin(), lgds.end(), 0.), lgds.end());

cplusplus.com/reference/algorithm/remove/

I suggest 2