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struct Line {
mutable ll m, c, p;
bool operator<(const Line& o) const {return m < o.m;}
bool operator<(ll x) const {return p < x;}
};
struct HullDynamic : multiset<Line, less<>> { // max über Geraden
// (for doubles, use INF = 1/.0, div(a,c) = a/c)
ll div(ll a, ll c) {return a / c - ((a ^ c) < 0 && a % c);}
bool isect(iterator x, iterator y) {
if (y == end()) {x->p = INF; return false;}
if (x->m == y->m) x->p = x->c > y->c ? INF : -INF;
else x->p = div(y->c - x->c, x->m - y->m);
return x->p >= y->p;
}
void add(ll m, ll c) {
auto x = insert({m, c, 0});
while (isect(x, next(x))) erase(next(x));
if (x != begin()) {
x--;
if (isect(x, next(x))) {
erase(next(x));
isect(x, next(x));
}}
while (x != begin() && prev(x)->p >= x->p) {
x--;
isect(x, erase(next(x)));
}}
ll query(ll x) {
auto l = *lower_bound(x);
return l.m * x + l.c;
}
};
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