Submission #1236480

#	Time	Username	Problem	Language	Result	Execution time	Memory
1236480		duckindog	Long Distance Coach (JOI17_coach)	C++20	0 / 100	2 ms	4936 KiB

coach

#include <bits/stdc++.h>

using namespace std;

#define int long long

const int N = 200'000 + 10;
int x, n, m, w, t;
int s[N];
int d[N], c[N];

int prefC[N];
int ame[N];
int f[N];

struct Line { 
    int a, b;
    Line(int a = 0, int b = 0) : a(a), b(b) {}
    double x(const Line& rhs) { 
        return 1.0 * (a - rhs.a) / (rhs.b - b); 
    }
};
namespace CHT { 
    int top;
    Line line[N];
    void add(Line nLine) { 
        while (top > 1 && line[top - 2].x(nLine) > line[top - 2].x(line[top - 1])) top -= 1;
        line[top++] = nLine;
    }
}


int32_t main() { 
    cin.tie(0)->sync_with_stdio(0);

    cin >> x >> n >> m >> w >> t;
    for (int i = 1; i <= n; ++i) cin >> s[i];
    for (int i = 1; i <= m; ++i) cin >> d[i] >> c[i];
    
    s[++n] = x;
    sort(s + 1, s + n + 1);
    { // sort by D
        vector<int> nD(d, d + m + 1), nC(c, c + m + 1);
        vector<int> order(m); iota(order.begin(), order.end(), 1);
        sort(order.begin(), order.end(), [&](const auto& a, const auto& b) { 
            return d[a] < d[b];
        });
        for (int i = 0; i < m; ++i) { 
            d[i + 1] = nD[order[i]];
            c[i + 1] = nC[order[i]];
        }
    }

    { // cal ame
        vector<pair<int, int>> vt;
        for (int i = 1; i <= m; ++i) vt.push_back({d[i], i});
        for (int i = 1; i <= n; ++i) vt.push_back({s[i] % t, -i});
        sort(vt.begin(), vt.end());

        fill(ame + 1, ame + m + 1, n + 2);
        int last = 0;
        for (const auto& [p, idx] : vt) { 
            if (idx > 0) last = idx;
            else ame[last] = min(ame[last], -idx);
        }
        for (int i = 1; i <= m; ++i) {
            if (ame[i] == n + 2) ame[i] = 0;
            
            prefC[i] = prefC[i - 1] + c[i];
        }
    }

    memset(f, 14, sizeof f);
    f[0] = 0;
    for (int i = 1; i <= m; ++i) { 
        auto& ret = f[i];

        CHT::add(Line(-i, f[i - 1] - prefC[i - 1]));
        { // take
            ret = min(ret, f[i - 1] + ((x - d[i] - 1) / t + 1) * w);
        }
        if (ame[i]) { // no take
            const int x = (s[ame[i]] - 1) / t * w;
            auto cal = [&](int mid) { 
                return (i + CHT::line[mid].a + 1) * x + CHT::line[mid].b + prefC[i];
            };

            int l = 0, r = CHT::top - 1, it = 0;
            while (l <= r) { 
                int mid = (l + r) >> 1;
                if (cal(mid + 1) <= cal(mid)) l = it = mid + 1;
                else r = mid - 1;
            }
            ret = min(ret, cal(it));
        }
    }
    int add = ((x - 1) / t + 1) * w;

    cout << f[m] + add << "\n";
}

• Subtask 1: 0 / 16
• Subtask 2: 0 / 30
• Subtask 3: 0 / 25
• Subtask 4: 0 / 29