제출 #485378

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
485378		PoPularPlusPlus	Olympic Bus (JOI20_ho_t4)	C++17	100 / 100	293 ms	5556 KiB

ho_t4

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long 
#define pb(e) push_back(e)
#define sv(a) sort(a.begin(),a.end())
#define sa(a,n) sort(a,a+n)
#define mp(a,b) make_pair(a,b)
#define vf first
#define vs second
#define ar array
#define all(x) x.begin(),x.end()
const int inf = 0x3f3f3f3f;
const int mod = 1000000007; 
const double PI=3.14159265358979323846264338327950288419716939937510582097494459230;
bool remender(ll a , ll b){return a%b;}

const int N = 203;
vector<ar<ll,3>> adj[N];
ll dis[N];
vector<ar<ll,4>> v;

void Dijkstra(ll e , int idx){
	 priority_queue< pair<ll,ll>, vector <pair<ll,ll>> , greater<pair<ll,ll>> > pq; 
	 dis[e]=0;
	 pq.push({0,e});
	 while(!pq.empty()){
		 ll node = pq.top().second,ww=pq.top().first;
		 pq.pop();
		 if(dis[node] < ww)continue;
		 for(auto i : adj[node]){
			 if(i[2] == idx)continue;
			 ll w = i[1];
			 if(dis[i[0]] > dis[node] + w){
				 dis[i[0]] = dis[node] + w;
				 pq.push({dis[i[0]],i[0]});
			 }
		 }
		 if(node == v[idx][1]){
			 ll w = v[idx][2];
			 if(dis[v[idx][0]] > dis[node] + w){
				dis[v[idx][0]] = dis[node] + w;
				pq.push({dis[v[idx][0]],v[idx][0]}); 
			 }
		 }
	 }
}

void solve(){
	int n , m;
	cin >> n >> m;
	ll fw[n][n];
	for(int i = 0; i < n; i++){
		for(int j = 0; j < n; j++){
			if(i == j)fw[i][j] = 0;
			else fw[i][j] = 1e18;
		}
	}
	for(int i = 0; i < m; i++){
		ll a , b , c , d;
		cin >> a >> b >> c >> d;
		a--;
		b--;
		adj[a].push_back({b,c,i});
		v.push_back({a,b,c,d});
		fw[a][b] = min(fw[a][b] , c);
	}
	for(int i = 0; i < n; i++){
		for(int j = 0; j < n; j++){
			for(int k =0 ; k < n; k++){
				fw[j][k] = min(fw[j][k] , fw[j][i] + fw[i][k]);
			}
		}
	}
	ll ans = fw[0][n-1] + fw[n-1][0];
	for(int i = 0; i < m; i++){
		ll res = min(fw[0][n-1] , fw[0][v[i][1]] + fw[v[i][0]][n-1]) + min(fw[n-1][0] , fw[n-1][v[i][1]] + fw[v[i][0]][0]) + v[i][3] + v[i][2];
		if(res < ans){
			for(int j = 0; j < n; j++)dis[j] = 1e18;
			Dijkstra(0 , i);
			res = dis[n-1];
			for(int j = 0; j < n; j++)dis[j] = 1e18;
			Dijkstra(n-1 , i);
			res += dis[0];
			res += v[i][3];
			ans = min(ans , res);
		}
	}
	cout << (ans >= 1e18 ? -1 : ans) << '\n';
}

int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
	//int t;cin >> t;while(t--)
	solve();
	return 0;
}

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