Submission #623655

#	Time	Username	Problem	Language	Result	Execution time	Memory
623655		valerikk	Escape Route (JOI21_escape_route)	C++17	35 / 100	9089 ms	133856 KiB

escape_route

#include "escape_route.h"
#include <algorithm>
#include <cassert>
#include <limits>

static const long long INF = 1e18;
static const int MAX_N = 60;
static const int MAX_M = 1770;

std::vector<long long> calculate_necessary_time(
	int N, int M, long long S, int Q, std::vector<int> A, std::vector<int> B,
	std::vector<long long> L, std::vector<long long> C, std::vector<int> U,
	std::vector<int> V, std::vector<long long> T) {

	std::vector<long long> answer(Q, INF);

	std::vector<std::vector<long long>> dists0(N);
	for (int start = 0; start < N; ++start) {
		std::vector<std::vector<long long>> l(N, std::vector<long long>(N, -1));
		std::vector<std::vector<long long>> c(N, std::vector<long long>(N, -1));
		for (int i = 0; i < M; ++i) {
			l[A[i]][B[i]] = l[B[i]][A[i]] = L[i];
			c[A[i]][B[i]] = c[B[i]][A[i]] = C[i];	
		}

		std::vector<long long> dist(N, INF);
		std::vector<bool> used(N, false);
		dist[start] = 0;
		for (int it = 0; it < N; ++it) {
			int u = -1;
			for (int v = 0; v < N; ++v) {
				if (!used[v] && (u == -1 || dist[v] < dist[u])) {
					u = v;
				}
			}
			assert(dist[u] != INF);
			used[u] = true;
			long long rem = dist[u] % S;
			for (int v = 0; v < N; ++v) {
				if (!used[v] && l[u][v] != -1) {
					long long new_dist = dist[u] + l[u][v];
					if (rem + l[u][v] > c[u][v]) {
						new_dist = dist[u] + S - rem + l[u][v];
					}
					dist[v] = std::min(dist[v], new_dist);
				}
			}
		}
		dists0[start] = dist;
	}

	for (int start = 0; start < N; ++start) {
		std::vector<std::vector<long long>> l(N, std::vector<long long>(N, -1));
		std::vector<std::vector<long long>> c(N, std::vector<long long>(N, -1));
		for (int i = 0; i < M; ++i) {
			l[A[i]][B[i]] = l[B[i]][A[i]] = L[i];
			c[A[i]][B[i]] = c[B[i]][A[i]] = C[i];	
		}

		std::vector<long long> stops = {0};
		static long long dists[2 * MAX_M + 1][MAX_N];
		while (true) {
			static long long dist[MAX_N];
			static bool used[MAX_N];
			std::fill(dist, dist + N, INF);
			std::fill(used, used + N, false);
			dist[start] = 0;
			for (int it = 0; it < N; ++it) {
				int u = -1;
				for (int v = 0; v < N; ++v) {
					if (!used[v] && (u == -1 || dist[v] < dist[u])) {
						u = v;
					}
				}
				if (dist[u] == INF) break;
				used[u] = true;
				for (int v = 0; v < N; ++v) {
					if (!used[v] && l[u][v] != -1) {
						dist[v] = std::min(dist[v], dist[u] + l[u][v]);
					}
				}
			}
			long long stop = INF;
			for (int u = 0; u < N; ++u) {
				for (int v = 0; v < N; ++v) {
					if (l[u][v] != -1) {
						stop = std::min(stop, std::max(stops.back(), c[u][v] - dist[u] - l[u][v] + 1));
					}
				}
			}
			std::copy(dist, dist + N, dists[(int) stops.size() - 1]);
			stops.push_back(stop);
			for (int u = 0; u < N; ++u) {
				for (int v = 0; v < N; ++v) {
					if (l[u][v] != -1 && std::max(stops.back(), c[u][v] - dist[u] - l[u][v] + 1) == stop) {
						l[u][v] = -1;
						c[u][v] = -1;
					}
				}
			}
			if (stop == INF) break;
		}

		for (int i = 0; i < Q; ++i) {
			if (U[i] == start) {
				int pos = std::upper_bound(begin(stops), end(stops), T[i]) - begin(stops);
				answer[i] = std::min(answer[i], dists[pos - 1][V[i]]);
				for (int W = 0; W < N; ++W) {
					if (dists[pos - 1][W] != INF) {
						answer[i] = std::min(answer[i], S - T[i] + dists0[W][V[i]]); 
					}
				}
			}
		}
	}

	return answer;
}

• Subtask 1: 5 / 5
• Subtask 2: 20 / 20
• Subtask 3: 10 / 10
• Subtask 4: 0 / 35
• Subtask 5: 0 / 30