If you drop the use of pointers (which are overkill for your simple structures), then you can use std::greater
from the header functional
:
std::priority_queue<Plane, std::vector<Plane>, std::greater<Plane> > pq1;
pq1.push(Plane(0, 0));
Currently, you are feeding Plane
as the comparison type. That won't work since the comparison type must be a type of function object, i.e. it must have an operator()
that does the comparison. Plane
doesn't have such a member (and adding it just for this purpose would be a bad idea).
std::greater
has the appropriate method, implemented in terms of your operator>
. However, it doesn't work with pointers, because then it uses a pointer comparison (based on memory addresses).
Btw., note that your comparison function can be expressed more succinctly as
bool operator>(const Plane &other)
{
return fuel > other.fuel;
}