oj.uz

답안 #669546

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
669546 2022-12-06T17:27:39 Z four_specks Building Bridges (CEOI17_building) C++17
100 / 100
 48 ms 9812 KB 
#include <bits/stdc++.h>

using namespace std;

inline namespace
{
    template <typename T>
    T fl_div(T a, T b) { return a / b - ((a ^ b) < 0 && a % b); }

    template <typename T>
    struct Line
    {
        T m, c;
        T operator()(T x) const { return m * x + c; }
    };

    template <typename T>
    struct LineContainerObject
    {
        T m, c;
        mutable T p;

        bool operator<(const LineContainerObject &i_line) const { return m < i_line.m; }
        bool operator<(T x) const { return p < x; }
    };

    template <typename T>
    struct LineContainer : multiset<LineContainerObject<T>, less<>>
    {
        void add(const Line<T> &line)
        {
            auto it1 = Base::insert({line.m, line.c, 0}), it2 = next(it1), it = it1;
            while (isect(it1, it2))
                it2 = Base::erase(it2);
            if (it != Base::begin())
            {
                it--;
                if (isect(it, next(it)))
                    isect(it, Base::erase(next(it)));
            }
            while (it != Base::begin() && prev(it)->p >= it->p)
            {
                it--;
                isect(it, Base::erase(next(it)));
            }
        }

        T query(T x)
        {
            auto it = Base::lower_bound(x);
            return it->m * x + it->c;
        }

    private:
        using Base = multiset<LineContainerObject<T>, less<>>;
        using Iterator = typename Base::iterator;

        inline static const T INF = numeric_limits<T>::max();

        bool isect(Iterator it, Iterator it1)
        {
            if (it1 == Base::end())
            {
                it->p = INF;
                return 0;
            }

            if (it->m == it1->m)
                it->p = it->c > it1->c ? INF : -INF;
            else
                it->p = fl_div(it1->c - it->c, it->m - it1->m);

            return it->p >= it1->p;
        }
    };

} // namespace

void solve()
{
    int n;
    cin >> n;

    vector<long> h(n), w(n);
    for (long &x : h)
        cin >> x;
    for (long &x : w)
        cin >> x;

    long add = 0;
    for (long x : w)
        add += x;

    vector<long> dp(n);
    LineContainer<long> cht;
    dp[0] = w[0];
    cht.add(Line<long>{2 * h[0], dp[0] - h[0] * h[0]});
    for (int i = 1; i < n; i++)
    {
        dp[i] = cht.query(h[i]) - h[i] * h[i] + w[i];
        cht.add(Line<long>{2 * h[i], dp[i] - h[i] * h[i]});
    }

    cout << -dp[n - 1] + add << '\n';
}

int main()
{
    ios_base::sync_with_stdio(false), cin.tie(NULL);

    solve();

    return 0;
}

Subtask #1
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 328 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 37 ms 3772 KB Output is correct
2 Correct 37 ms 3744 KB Output is correct
3 Correct 40 ms 3680 KB Output is correct
4 Correct 33 ms 3532 KB Output is correct
5 Correct 33 ms 4680 KB Output is correct

Subtask #3
40.0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 328 KB Output is correct
6 Correct 37 ms 3772 KB Output is correct
7 Correct 37 ms 3744 KB Output is correct
8 Correct 40 ms 3680 KB Output is correct
9 Correct 33 ms 3532 KB Output is correct
10 Correct 33 ms 4680 KB Output is correct
11 Correct 35 ms 3800 KB Output is correct
12 Correct 37 ms 3656 KB Output is correct
13 Correct 28 ms 3796 KB Output is correct
14 Correct 40 ms 3788 KB Output is correct
15 Correct 48 ms 9812 KB Output is correct
16 Correct 35 ms 4700 KB Output is correct
17 Correct 23 ms 3668 KB Output is correct
18 Correct 19 ms 3680 KB Output is correct