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