Cod sursa(job #2705242)

Utilizator vlad_butnaruVlad Butnaru vlad_butnaru Data 12 februarie 2021 11:13:05
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.31 kb
#include <bits/stdc++.h>
using namespace std;
ifstream in ("dijkstra.in");
ofstream out ("dijkstra.out");
vector < pair <int , int> > v[50001];
int dist[50001];
int n,m;
void dijkstra (int start)
{
    set <pair < int , int> > seti;
    seti.insert ({0, start});
    dist[start] = 0;
    while (!seti.empty())
    {
        int place = (*seti.begin()).second;
        int cost = (*seti.begin()).first;
        seti.erase(seti.begin());
        for (int i = 0; i < v[place].size(); ++i)
        {
            if (dist[place] + v[place][i].second < dist[v[place][i].first])
            {
                if (dist[v[place][i].first] != 1<<30)
                    seti.erase(seti.find(make_pair(dist[v[place][i].first], v[place][i].first)));
                dist[v[place][i].first] = cost + v[place][i].second;
                seti.insert({dist[v[place][i].first], v[place][i].first});
            }
        }
    }
}
int main ()
{
    in >> n >> m;
    for (int i = 1;i<=m;++i)
    {
        int a,b,c;
        in>>a>>b>>c;
        v[a].push_back({b,c});
    }
    for (int i = 1; i<=n; ++i)
        dist[i] = 1<<30;
    dijkstra(1);
    for (int i = 2;i<=n;++i)
    {
        if (dist[i]==1<<30)
            out<< 0 << ' ';
        else
            out << dist[i] << ' ';
    }
    return 0;
}