• https://www.luogu.com.cn/problem/P4254
• https://darkbzoj.cc/problem/1568

这个 可真棒。。。

#define ll double
struct Line {
	mutable ll k, b, p;
	Line (ll k = 0, ll b = 0):k(k),b(b){
	    p = 0;
	}
	ll y(ll x) const {return k*x + b;}
	bool operator<(const Line& o) const { return k < o.k; }
	bool operator<(ll x) const { return p < x; }
};

struct LineContainer : multiset<Line,less<>> {
	const ll inf = 1/.0;
	ll div(ll a, ll b) {
		return a / b;
    }
	bool isect(iterator x, iterator y) {
		if (y == end()) return x->p = inf, 0;
		if (x->k == y->k) x->p = x->b > y->b ? inf : -inf;
		else x->p = div(y->b - x->b, x->k - y->k);
		return x->p >= y->p;
	}
	void add(ll k, ll b) {
		add(Line(k,b));
	}
	void add(Line t) {
		auto z = insert(t), 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) {
		assert(!empty());
		auto& l = *lower_bound(x);
		return l.y(x);
	}
} H;

int main(){

#ifndef ONLINE_JUDGE
    freopen("in.txt", "r", stdin);
    // freopen("out.txt", "w", stdout);
#endif

    H.add(0, 0); char cmd[10]; DB k, b, x; Rush {
        RS(cmd);
        if (cmd[0] == 'P') {
            RF(b, k);
            H.add(k, b);
        } else {
            RF(x);
            OT(LL(H.query(x-1)/100));
        }
    }
}

Posted by xiaodao
Category: 日常