Submission #1113373

#	Time	Username	Problem	Language	Result	Execution time	Memory
1113373		Dan4Life	Commuter Pass (JOI18_commuter_pass)	C++17	31 / 100	308 ms	25140 KiB

commuter_pass

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

#define pb push_back
#define sz(a) (int)a.size()
#define all(a) begin(a),end(a)

using vi = vector<int>;
using ll = long long;
using ar2 = array<ll,2>;

const int N = (int)2e5+10;
const int INF = (int)1e9;
const ll LINF = (ll)2e18;

int n, m, S, T, U, V;
ll dis[4][N];
vector<ar2> adj[N];

void dijkstra(int s, int t){
	priority_queue<ar2,vector<ar2>,greater<ar2>> pq;
	while(sz(pq)) pq.pop();
	for(int i = 1; i <= n; i++) dis[t][i]=LINF;
	dis[t][s] = 0; pq.push({0,s});
	while(sz(pq)){
		auto [D,a] = pq.top(); pq.pop();
		if(D!=dis[t][a]) continue;
		for(auto [b,w] : adj[a]){
			if(dis[t][a]+w<dis[t][b]){
				dis[t][b] = dis[t][a]+w;
				pq.push({dis[t][b],b});
			}
		}
	}
}

int main(){
	ios_base::sync_with_stdio(false); cin.tie(0);
	cin >> n >> m >> S >> T >> U >> V;
	for(int i = 0; i < m; i++){
		int a, b, c; cin >> a >> b >> c;
		adj[a].pb({b,c}), adj[b].pb({a,c});
	}
	dijkstra(S,0); dijkstra(T,1); 
	for(int i = 1; i <= n; i++)
		for(auto &[b,c] : adj[i])
			if(dis[0][i]+c+dis[1][b]==dis[0][T]
				or dis[0][b]+c+dis[1][i]==dis[0][T]) c=0;
	dijkstra(U,2); dijkstra(V,3);
	ll ans = dis[2][V];
	/*for(int i = 1; i <= n; i++){
		if(dis[0][i]+dis[1][i]!=dis[0][T]) continue;
		ans = min(ans, dis[3][i]);
	}*/
	cout << ans << "\n";
}

• Subtask 1: 16 / 16
• Subtask 2: 15 / 15
• Subtask 3: 0 / 24
• Subtask 4: 0 / 45