Submission #529113

#	Time	Username	Problem	Language	Result	Execution time	Memory
529113		rk42745417	Olympic Bus (JOI20_ho_t4)	C++17	0 / 100	37 ms	1212 KiB

ho_t4

#include <bits/stdc++.h>
using namespace std;

#define EmiliaMyWife ios::sync_with_stdio(0); cin.tie(0);
using ll = int64_t;
using ull = uint64_t;
using uint = uint32_t;
using ld = long double;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
const ll LINF = ll(4e18) + ll(2e15);
const double EPS = 1e-9;
static int LamyIsCute = []() {
	EmiliaMyWife
	return 48763;
}();

const int N = 207;
vector<pair<int, int>> edge[N];
void dijk(int s, vector<int> &dis) {
	dis[s] = 0;
	priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;
	pq.push({0, s});
	while(!pq.empty()) {
		auto [d, u] = pq.top();
		pq.pop();
		if(d > dis[u])
			continue;
		for(const auto &[v, c] : edge[u]) {
			if(dis[v] > dis[u] + c) {
				dis[v] = dis[u] + c;
				pq.push({dis[v], v});
			}
		}
	}
}

signed main() {
	int n, m;
	cin >> n >> m;
	vector<tuple<int, int, int, int>> edges;
	for(int i = 0; i < m; i++) {
		int u, v, c, d;
		cin >> u >> v >> c >> d;
		if(i % 2 == 0) {
			edge[u].push_back({v, c});
			edges.push_back({u, v, c, d});
		}
	}
	vector<vector<int>> dis(n + 1, vector<int>(n + 1, INF));
	for(int i = 1; i <= n; i++)
		dijk(i, dis[i]);
	int ans = INT_MAX;
	if(dis[1][n] < INF && dis[n][1] < INF)
		ans = min(ans, dis[1][n] + dis[n][1]);
	for(const auto &[u, v, c, d] : edges) {
		ans = min<ll>({
			ans,
			(dis[1][v] < INF && dis[u][n] < INF && dis[u][1] < INF ? dis[1][v] + dis[u][n] + c + dis[n][1] + d : INT_MAX),
			(dis[1][v] < INF && dis[u][n] < INF && dis[n][v] < INF && dis[u][1] < INF ? dis[1][v] + dis[u][n] + c + dis[n][v] + dis[u][1] + c + d : INT_MAX),
			(dis[1][n] < INF && dis[n][v] < INF && dis[u][1] < INF ? dis[1][n] + dis[n][v] + dis[u][1] + c + d : INT_MAX),
		});
	}
	if(ans == INT_MAX)
		cout << "-1\n";
	else
		cout << ans << '\n';
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 21
• Subtask 4: 0 / 63