Submission #41173

#	Time	Username	Problem	Language	Result	Execution time	Memory
41173		IvanC	Commuter Pass (JOI18_commuter_pass)	C++14	100 / 100	1073 ms	31740 KiB

commuter_pass

#include <bits/stdc++.h>
#define MT make_tuple
using namespace std;
const int MAXN = 1e5 + 10;
typedef long long ll;
typedef tuple<ll,ll,ll> trinca;
typedef pair<ll,ll> ii;
vector<ii> grafo[MAXN];
ll N,M,processado[MAXN][8],dist[MAXN][8],ans,S,T,U,V,menorcaminho;
void Dijskra(ll origem,ll idx){
	priority_queue<ii, vector<ii> , greater<ii> > pq;
	pq.push(ii(0,origem));
	while(!pq.empty()){
		ll percorrido = pq.top().first, v = pq.top().second;
		pq.pop();
		if(processado[v][idx]) continue;
		processado[v][idx] = 1;
		dist[v][idx] = percorrido;
		for(int i = 0;i<grafo[v].size();i++){
			ll u = grafo[v][i].first, w = grafo[v][i].second;
			if(!processado[u][idx]) pq.push(ii(w + percorrido,u));
		}
	}
}
void solve(ll origem,ll qualsoma,ll idx, ll qualminimiza, ll qualtenta ){
	priority_queue<trinca, vector<trinca> , greater<trinca> > pq;
	pq.push(MT(0,(ll)1e18,origem));
	while(!pq.empty()){
		trinca davez = pq.top();
		pq.pop();
		ll percorrido = get<0>(davez), menor = get<1>(davez) , v = get<2>(davez);
		if(processado[v][idx]) continue;
		processado[v][idx] = 1;
		dist[v][idx] = percorrido;
		if(percorrido + dist[v][qualsoma] == menorcaminho){
			ans = min(ans, menorcaminho + menor + dist[v][qualtenta] );
		}
		menor = min(menor,dist[v][qualminimiza]);
		for(int i = 0;i<grafo[v].size();i++){
			ll u = grafo[v][i].first, w = grafo[v][i].second;
			if(!processado[u][idx]) pq.push(MT(w + percorrido,menor,u));
		}
	}
}
int main(){
	cin.tie(0);ios_base::sync_with_stdio(0);
	cin >> N >> M >> S >> T >> U >> V;
	for(int i = 1;i<=M;i++){
		ll u,v,w;
		cin >> u >> v >> w;
		grafo[u].push_back(ii(v,w));
		grafo[v].push_back(ii(u,w));
	}
	Dijskra(S,0);
	Dijskra(T,1);
	Dijskra(U,2);
	Dijskra(V,3);
	ans = dist[T][0] + dist[V][2];
	menorcaminho = dist[T][0];
	solve(S,1,4,2,3);
	solve(S,1,5,3,2);
	solve(T,0,6,2,3);
	solve(T,0,7,3,2);
	cout << ans - menorcaminho << endl;
	return 0;
}

Compilation message (stderr)

commuter_pass.cpp: In function 'void Dijskra(ll, ll)':
commuter_pass.cpp:19:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0;i<grafo[v].size();i++){
                  ^
commuter_pass.cpp: In function 'void solve(ll, ll, ll, ll, ll)':
commuter_pass.cpp:39:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0;i<grafo[v].size();i++){
                  ^

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