Cod sursa(job #2749856)

Utilizator radubigColtos Radu radubig Data 8 mai 2021 16:23:01
Problema Algoritmul lui Dijkstra Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.33 kb
#include <fstream>
#include <set>
#include <vector>
#define lim 50000

using namespace std;
ifstream in("dijkstra.in");
ofstream out("dijkstra.out");
const int INF = 2e9;

vector<pair<int, int>> v[lim+5]; //first->nod, second->cost
int viz[lim+5], dist[lim+5];
int n, m;

void Dijkstra(int sursa)
{
    for(int i=1; i<=n; i++)
        dist[i] = INF;

    set<pair<int, int>> s; //first -> dist[nod], second -> nod
    dist[sursa] = 0;
    s.insert({0, sursa});
    while(!s.empty()) //sau while(s.size()>0)
    {
        int nod = s.begin()->second;
        s.erase(s.begin());
        if(viz[nod]==0)
        {
            viz[nod] = 1;
            for(auto& i : v[nod])
            {
                int vecin = i.first;
                int cost = i.second;
                if(dist[nod] + cost < dist[vecin])
                {
                    dist[vecin] = dist[nod] + cost;
                    s.insert({dist[vecin], vecin});
                }
            }
        }
    }
}

int main()
{
    in>>n>>m;
    for(int i=1; i<=m; i++)
    {
        int x, y, c;
        in>>x>>y>>c;
        v[x].push_back({y, c});
        v[y].push_back({x, c});
    }

    Dijkstra(1);

    for(int i=2; i<=n; i++)
    {
        if(dist[i] != INF) out<<dist[i]<<' ';
        else out<<"0 ";
    }
    return 0;
}