Cod sursa(job #2807482)

Utilizator StefaniaCriStefania Cristea StefaniaCri Data 23 noiembrie 2021 20:49:51
Problema Algoritmul lui Dijkstra Scor 90
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.42 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>

using namespace std;
#define Nmax 50008

int n,m;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
#define inf 200004

void dijkstra(vector< pair<int,int> > node_with_cost[Nmax],int source)
{

    vector<int> dist(n+1,inf);
    vector<bool> visited(n+1,false);
    priority_queue<pair<int,int>,
        vector<pair<int,int>>,
        greater< pair<int,int> > > pq;

    dist[source]=0;

    pq.push(make_pair(0,source));
    while(!pq.empty())
    {
        int poz=pq.top().first;
        int u=pq.top().second;
        pq.pop();
        if(visited[u]) continue;
        visited[u]=false;
        for(auto i=node_with_cost[u].begin();
            i!=node_with_cost[u].end();++i)
        {
            int v=(*i).first;
            int weight = (*i).second;
            if(dist[v]>dist[u]+weight)
            {
                dist[v]=dist[u]+weight;
                pq.push(make_pair(dist[v],v));
            }
        }
    }
    for(int i=2;i<=n;i++)
        if(dist[i]!=inf)
            g<<dist[i]<<" ";
         else g<<0<<" ";
}

int main()
{

    vector< pair<int,int> > node_with_cost[Nmax];
    f>>n>>m;

    for(int i=0;i<m;i++)
    {
        int x,y,cost;
        f>>x>>y>>cost;
        node_with_cost[x].push_back(make_pair(y,cost));

    }

    dijkstra(node_with_cost,1);

    return 0;
}