Cod sursa(job #2681428)

Utilizator CleliaClelia Maria Dobrescu Clelia Data 5 decembrie 2020 14:17:08
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.32 kb
#include <bits/stdc++.h>
using namespace std;
ifstream fin ("dijkstra.in");
ofstream fout ("dijkstra.out");
int n,m;
const int MAX_N=50000;
const int INF=1e9;
vector <pair <int,int> > gr[1+MAX_N];
int dist[1+MAX_N];
bool viz[1+MAX_N];
void runDijkstra (int source)
{
    for (int i=1;i<=n;i++)
        dist[i]=INF;
    priority_queue <pair <int,int> > minDistances;
    dist[source]=0;
    minDistances.push({0,source});
    while (minDistances.size()>0)
    {
        int node=minDistances.top().second;
        minDistances.pop();
        if (viz[node]==false)
        {
            viz[node]=true;
            for (int i=0;i<gr[node].size();i++)
            {
                int vec=gr[node][i].first;
                int cost=gr[node][i].second;
                if (dist[node]+cost<dist[vec])
                {
                    dist[vec]=dist[node]+cost;
                    minDistances.push({-dist[vec],vec});
                }
            }
        }
    }
}
int main ()
{
    fin>>n>>m;
    for (int i=1;i<=m;i++)
    {
        int x,y,cost;
        fin>>x>>y>>cost;
        gr[x].push_back({y,cost});
    }
    runDijkstra(1);
    for (int i=2;i<=n;i++)
    {
        if (dist[i]!=INF)
            fout<<dist[i]<<" ";
        else
            fout<<0<<" ";
    }
    return 0;
}