Submission #1265287

#	Time	Username	Problem	Language	Result	Execution time	Memory
1265287		vlomaczk	Olympic Bus (JOI20_ho_t4)	C++20	0 / 100	21 ms	2748 KiB

ho_t4

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
typedef long long ll;
using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

struct Edge {
	ll a, b, c, d;
};

ll n, m;
ll M = 210, inf = 1e17;
vector<vector<ll>> dist(M, vector<ll>(M, inf));
vector<Edge> e;

void floyd() {
	for(int k=1; k<=n; ++k) {
		for(int i=1; i<=n; ++i) {
			for(int j=1; j<=n; ++j) {
				if(dist[i][k] < inf && dist[k][j] < inf) dist[i][j] = min(dist[i][j], dist[i][k] + dist[k][j]);
			}
		}
	}
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);

	cin >> n >> m;
	for(int i=1; i<=n; ++i) dist[i][i] = 0;
	for(ll i=0; i<m; ++i) {
		Edge x;
		cin >> x.a >> x.b >> x.c >> x.d;
		dist[x.a][x.b] = min(dist[x.a][x.b], x.c);
		e.emplace_back(x);
	}
	floyd();
	ll ans = dist[1][n] + dist[n][1];
	for(auto[a, b, c, d] : e) {
		ll to = min(dist[1][n], dist[1][b] + c + d + dist[a][n]);
		ll from = min(dist[n][1], dist[n][b] + c + d + dist[a][1]);
		ans = min(ans, to+from);
	}
	if(ans >= inf) cout << "-1\n";
	else cout << ans << "\n";

	return 0;
}

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