Submission #666923

#	Time	Username	Problem	Language	Result	Execution time	Memory
666923		Markomafko972	Commuter Pass (JOI18_commuter_pass)	C++14	31 / 100	770 ms	30048 KiB

commuter_pass

#include <bits/stdc++.h>
#define X first
#define Y second
#define pb push_back
#define pii pair<int, int>
typedef long long ll;
using namespace std;

const int MOD = 1e9 + 7;
const ll INF = 1e18;
const int OFF = (1 << 20);

int n, m, a, b, c;
int poc1, kr1, poc2, kr2;
vector< pair<int, int> > v[100005];
set< pair<ll, int> > s;
ll dist[100005];
vector<int> gdje[100005];
int bio[100005];

void dijkstra() {
	
	while (!s.empty()) {
		ll cost = s.begin() -> first;
		int cvor = s.begin() -> second;
		s.erase(s.begin());
		
		for (int i = 0; i < v[cvor].size(); i++) {
			int sus = v[cvor][i].X;
			int d = v[cvor][i].Y;
			
			if (cost+d < dist[sus]) {
				s.erase({dist[sus], sus});
				dist[sus] = cost+d;
				s.insert({dist[sus], sus});
				gdje[sus].clear();
				gdje[sus].push_back(cvor);
			}
			else if (cost+d == dist[sus]) {
				gdje[sus].push_back(cvor);
			}
		}
	}
	
}

void dfs(int x) {
	if (bio[x] == 1) return;
	bio[x] = 1;
	
	for (int i = 0; i < gdje[x].size(); i++) {
		v[gdje[x][i]].push_back({x, 0});
		dfs(gdje[x][i]);
	}
}

int main () {

	ios_base::sync_with_stdio(false);
	cin.tie(0);
	
	cin >> n >> m;
	cin >> poc1 >> kr1;
	cin >> poc2 >> kr2;
	for (int i = 0; i < m; i++) {
		cin >> a >> b >> c;
		v[a].push_back({b, c});
		v[b].push_back({a, c});
	}
	
	for (int i = 1; i <= n; i++) {
		if (i != poc1) dist[i] = INF;
		s.insert({dist[i], i});
	}
	dijkstra();
	dfs(kr1);
	
	for (int i = 1; i <= n; i++) {
		if (i != poc2) dist[i] = INF;
		else dist[i] = 0;
		s.insert({dist[i], i});
	}
	dijkstra();
	ll sol = dist[kr2];
	
	for (int i = 1; i <= n; i++) {
		if (i != kr2) dist[i] = INF;
		else dist[i] = 0;
		s.insert({dist[i], i});
	}
	dijkstra();
	sol = min(sol, dist[poc2]);
	
	cout << sol;

	return 0;
}

Compilation message (stderr)

commuter_pass.cpp: In function 'void dijkstra()':
commuter_pass.cpp:28:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |   for (int i = 0; i < v[cvor].size(); i++) {
      |                   ~~^~~~~~~~~~~~~~~~
commuter_pass.cpp: In function 'void dfs(int)':
commuter_pass.cpp:51:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |  for (int i = 0; i < gdje[x].size(); i++) {
      |                  ~~^~~~~~~~~~~~~~~~

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