Submission #710637

#	Time	Username	Problem	Language	Result	Execution time	Memory
710637		Cyanmond	Meetings (IOI18_meetings)	C++17	19 / 100	5550 ms	6004 KiB

meetings

#include "meetings.h"
#include <bits/stdc++.h>

using i64 = long long;
constexpr i64 inf = 1ll << 50;

std::vector<i64> solve(const std::vector<i64> &H) {
    const int N = (int)H.size();
    std::vector<i64> valList(N);
    std::stack<std::pair<int, i64>> stk;
    i64 sum = 0;
    for (int i = 0; i < N; ++i) {
        // update
        int u = 1;
        while ((not stk.empty()) and (stk.top().second <= H[i])) {
            sum -= stk.top().second * stk.top().first;
            u += stk.top().first;
            stk.pop();
        }
        stk.push({u, H[i]});
        sum += u * H[i];
        valList[i] = sum;
    }
    return valList;
}

std::vector<long long> minimum_costs(std::vector<int> H, std::vector<int> L,
                                     std::vector<int> R) {
    int N = (int)H.size(), Q = (int)L.size();
    std::vector<i64> answer(Q);
    for (int i = 0; i < Q; ++i) {
        std::vector<i64> h(R[i] - L[i] + 1);
        for (int j = L[i]; j <= R[i]; ++j) h[j - L[i]] = H[j];
        const auto x = solve(h);
        std::reverse(h.begin(), h.end());
        auto y = solve(h);
        std::reverse(y.begin(), y.end());
        for (int j = L[i]; j <= R[i]; ++j) y[j - L[i]] -= H[j];
        i64 res = inf;
        for (int j = 0; j < (R[i] - L[i] + 1); ++j) {
            res = std::min(res, x[j] + y[j]);
        }
        answer[i] = res;
    }
    return answer;
}

Compilation message (stderr)

meetings.cpp: In function 'std::vector<long long int> minimum_costs(std::vector<int>, std::vector<int>, std::vector<int>)':
meetings.cpp:29:9: warning: unused variable 'N' [-Wunused-variable]
   29 |     int N = (int)H.size(), Q = (int)L.size();
      |         ^

• Subtask 1: 4 / 4
• Subtask 2: 15 / 15
• Subtask 3: 0 / 17
• Subtask 4: 0 / 24
• Subtask 5: 0 / 40