Submission #923060

#	Time	Username	Problem	Language	Result	Execution time	Memory
923060		vjudge1	Olympic Bus (JOI20_ho_t4)	C++17	5 / 100	1097 ms	9076 KiB

ho_t4

//author : FatihCihan
#include <bits/stdc++.h>
using namespace std;
#define all(v) v.begin() , v.end()
#define sz(a) (int)a.size()
#define int long long
const int inf = 1e18 + 7;
void solve(){
	int n,m;
	cin >> n >> m;
	vector < vector < pair < int , int > > > graph(n+1) , igraph(n+1);
	array < int , 4 > edge[m];
	bool is_in_path[m];
	memset(is_in_path , 0 , sizeof(is_in_path));
	for(int i = 0;i<m;i++){
		cin >> edge[i][0] >> edge[i][1] >> edge[i][2] >> edge[i][3];
		graph[edge[i][0]].push_back({edge[i][1] , i});
		igraph[edge[i][1]].push_back({edge[i][0] , i});
	}
	auto eval = [&](int st , vector < vector < pair < int , int > > > G , int forbidden){
		vector < int > vis(n+1 , inf);
		priority_queue < array < int , 3 > > pq;
		pq.push({0 , st , -1});//3. buraya geldigim edge numarasi
		while(pq.size()){
			array < int , 3 >  tmp = pq.top();//dist , node , past edge
			pq.pop();
			if(vis[tmp[1]] != inf)continue;
			vis[tmp[1]] = -tmp[0];
			if(forbidden == -1 and tmp[2] != -1)is_in_path[tmp[2]] = 1;
			for(int i = 0;i<sz(G[tmp[1]]);i++){
				pair < int , int > itr = G[tmp[1]][i];
				if(itr.second == forbidden)continue;
				pq.push({tmp[0] - edge[itr.second][2], itr.first , itr.second});
			}
		}
		return vis;
	};
	vector < int > from1 = eval(1 , graph , -1);;
	vector < int > fromn = eval(n , graph , -1);
	vector < int > to1 = eval(1 , igraph , -1);
	vector < int > ton = eval(n , igraph , -1);
	int ans = from1[n] + fromn[1];
	for(int i = 0;i<m;i++){
		int r1 , r2;
		if(is_in_path[i]){
			// cout << "special : " << edge[i][0] << " " << edge[i][1] << " " << edge[i][2] << " " << edge[i][3] << endl;
			vector < int > tfrom1 = eval(1 , graph , i);
			vector < int > tfromn = eval(n , graph , i);
			vector < int > tto1 = eval(1 , igraph , i);
			vector < int > tton = eval(n , igraph , i);
			// cout << "tfrom1 : ";for(int i = 1;i<=n;i++)cout << tfrom1[i] << " ";cout << endl;
			// cout << "tfromn : ";for(int i = 1;i<=n;i++)cout << tfromn[i] << " ";cout << endl;
			// cout << "tto1 : ";for(int i = 1;i<=n;i++)cout << tto1[i] << " ";cout << endl;
			// cout << "tton : ";for(int i = 1;i<=n;i++)cout << tton[i] << " ";cout << endl;
			r1 = min(tfrom1[n] , tfrom1[edge[i][1]] + edge[i][2] + tton[edge[i][0]]);//gidis
			r2 = min(tfromn[1] , tfromn[edge[i][1]] + edge[i][2] + tto1[edge[i][0]]);//donus
			// cout << "r : " << r1 << " " << r2 << endl;
		}
		else{
			// cout << "ordinary : " << edge[i][0] << " " << edge[i][1] << " " << edge[i][2] << " " << edge[i][3] << endl;
			r1 = min(from1[n] , from1[edge[i][1]] + edge[i][2] + ton[edge[i][0]]);//gidis
			r2 = min(fromn[1] , fromn[edge[i][1]] + edge[i][2] + to1[edge[i][0]]);//donus
			// cout << "r : " << r1 << " " << r2 << endl;
		}
		ans = min(ans , edge[i][3] + r1 + r2);
	}
	cout << (ans >= inf ? -1 : ans) << endl;
}
signed main(){
	ios_base::sync_with_stdio(0);cin.tie(0);
	int testcase = 1;//cin >> testcase;
	while(testcase--)solve();
	cerr << 1000.0 * clock() / CLOCKS_PER_SEC << " ms" << endl;
}

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