Submission #1247062

#	Time	Username	Problem	Language	Result	Execution time	Memory
1247062		linusvdv	Overtaking (IOI23_overtaking)	C++20	39 / 100	3594 ms	560 KiB

overtaking

#include "overtaking.h"
#include <map>
#include <vector>

int l, n, m, x;
std::vector<long long> t;
std::vector<int> w;
std::vector<int> s;

void init(int L, int N, std::vector<long long> T, std::vector<int> W, int X, int M, std::vector<int> S)
{
    l = L; n = N; m = M; x = X;
    t = T; w = W; s = S;
}

long long arrival_time(long long Y)
{
    //              time, speed,     id
    std::map<std::pair<long long, int>, int> start_time;
    for (int i = 0; i < n; i++) {
        if (w[i] <= x) continue;
        start_time.insert({{t[i], w[i]}, i});
    }
    // reserve bus
    start_time.insert({{Y, x}, n});

    // go over bussesstops
    for (int i = 1; i < m; i++) {
        long long disdiff = s[i] - s[i-1];
        std::map<std::pair<long long, int>, int> stop_times;
        for (auto [ab, id] : start_time) {
            auto [time, slope] = ab;
            if (stop_times.upper_bound({time + disdiff*slope, slope}) == stop_times.end()) {
                long long idx = time + disdiff*slope;
                stop_times[{idx, slope}] = std::max(id, stop_times[{idx, slope}]);
            }
            else {
                long long idx = stop_times.rbegin()->first.first;
                stop_times[{idx, slope}] = std::max(id, stop_times[{idx, slope}]);
            }
        }
        std::swap(start_time, stop_times);
    }
    for (auto [ab, id] : start_time) {
        auto [time, slope] = ab;
        if (id == n) {
            return time;
        }
    }
    return -1;
}

• Subtask 0: 0 / 0
• Subtask 1: 9 / 9
• Subtask 2: 10 / 10
• Subtask 3: 20 / 20
• Subtask 4: 0 / 26
• Subtask 5: 0 / 35