int halfplane(lines &v, points &res) {
sort(v.begin(), v.end(), cmpang);
deque<line> q;
deque<point> ans;
q.push_back(v[0]);
for (int i = 1; i < int(v.size()); i ++) {
if (dcmp(v[i].ang - v[i - 1].ang) == 0) continue;
while(ans.size() && !onleft(ans.back(), v[i])) {
ans.pop_back();
q.pop_back();
}
while(ans.size() && !onleft(ans.front(), v[i])) {
ans.pop_front();
q.pop_front();
}
ans.push_back(interpoint(q.back(), v[i]));
q.push_back(v[i]);
}
while(ans.size() && !onleft(ans.back(), q.front())) {
ans.pop_back();
q.pop_back();
}
while(ans.size() && !onleft(ans.front(), q.back())) {
ans.pop_front();
q.pop_front();
}
ans.push_back(interpoint(q.back(), q.front()));
res = points(ans.begin(), ans.end());
return ans.size(); //you must use the size to assure an empty set, area dont has the accuracy we need
}
task4_6::solution::solution( const lines& calulator_lines )
{
for (size_t i = 0; i < calulator_lines.size(); ++i) {
try {
calculator_.CalculateExpression(calulator_lines[i]);
} catch (std::logic_error& e) {
std::stringstream msg;
msg << e.what() << "(line: " << i << ')';
throw std::logic_error(msg.str());
}
}
}