Submission #682745

#	Time	Username	Problem	Language	Result	Execution time	Memory
682745		Markomafko972	Commuter Pass (JOI18_commuter_pass)	C++14	100 / 100	679 ms	35276 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, poc1, poc2, kr1, kr2, a, b, c;
vector< pair<int, int> > v[100005];
ll dist[2][100005];
set< pair<ll, int> > s;

ll udl[100005];
ll mini[100005];

int bio[100005];
pair< pair<ll, ll>, ll> rj[100005];

vector<int> e[100005];

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

void dijk() {
	
	while (!s.empty()) {
		int cvor = s.begin() -> second;
		ll cost = s.begin() -> first;
		s.erase(s.begin());
		
		for (int i = 0; i < v[cvor].size(); i++) {
			int sus = v[cvor][i].X;
			int cijena = v[cvor][i].Y;
			
			if (cost+cijena < udl[sus]) {
				s.erase({udl[sus], sus});
				udl[sus] = cost+cijena;
				s.insert({udl[sus], sus});
			
				mini[sus] = min(mini[cvor], dist[1][sus]);
				e[sus].clear();
				e[sus].push_back(cvor);
			}
			else if (cost+cijena == udl[sus]) {
				mini[sus] = min(mini[sus], mini[cvor]);
				e[sus].push_back(cvor);
			}
		}
	}
	
}

pair<pair<ll, ll>, ll> dfs(int x) {
	bio[x] = 1;
	ll minx = dist[0][x], miny = dist[1][x], minsve = INF;
	
	for (int i = 0; i < e[x].size(); i++) {
		if (bio[e[x][i]] == 0) {
			dfs(e[x][i]);
		}
		
		pair< pair<ll ,ll>, ll > tren = rj[e[x][i]];
		minx = min(minx, tren.X.X);
		miny = min(miny, tren.X.Y);
		minsve = min(minsve, tren.Y);
	}
	
	rj[x] = {{minx, miny}, min({minx+dist[1][x], miny+dist[0][x], minsve})};
	return rj[x];
}

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++) {
		dist[0][i] = INF;
		if (i == poc2) dist[0][i] = 0;
		s.insert({dist[0][i], i});
	}
	dijkstra(0);

	for (int i = 1; i <= n; i++) {
		dist[1][i] = INF;
		if (i == kr2) dist[1][i] = 0;
		s.insert({dist[1][i], i});
	}
	dijkstra(1);
	for (int i = 1; i <= n; i++) mini[i] = dist[1][i];
	
	for (int i = 1; i <= n; i++) {
		udl[i] = INF;
		if (i == poc1) udl[i] = 0;
		s.insert({udl[i], i});
	}
	dijk();
	ll sold = dfs(kr1).Y;
	cout << min(sold, dist[0][kr2]);

	return 0;
}

Compilation message (stderr)

commuter_pass.cpp: In function 'void dijkstra(int)':
commuter_pass.cpp:33:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |   for (int i = 0; i < v[cvor].size(); i++) {
      |                   ~~^~~~~~~~~~~~~~~~
commuter_pass.cpp: In function 'void dijk()':
commuter_pass.cpp:54:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |   for (int i = 0; i < v[cvor].size(); i++) {
      |                   ~~^~~~~~~~~~~~~~~~
commuter_pass.cpp: In function 'std::pair<std::pair<long long int, long long int>, long long int> dfs(int)':
commuter_pass.cpp:80:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   80 |  for (int i = 0; i < e[x].size(); i++) {
      |                  ~~^~~~~~~~~~~~~

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