Cod sursa(job #2451918)

Utilizator filicriFilip Crisan filicri Data 28 august 2019 19:34:09
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.06 kb
#include <fstream>
#include <vector>
#include <queue>
#define lim 50004
#define inf 2000000000
using namespace std;

ifstream f("dijkstra.in");
ofstream g("dijkstra.out");

int n, m, a, b, c, dist[lim];
bool seen[lim];
vector<pair<int, int> > G[lim];
priority_queue<pair<int, int> > pq;

int main() {

    f>>n>>m;
    for(int i=1;i<=m;i++) {
        f>>a>>b>>c;
        G[a].push_back({b,c});
    }

    for(int i=2;i<=n;i++)
        dist[i]=inf;

    pq.push({0, 1});
    while(!pq.empty()) {
        int currNode=pq.top().second;
        pq.pop();
        if(!seen[currNode]) {
            seen[currNode]=1;
            for(auto ne:G[currNode])
                if(dist[currNode]+ne.second<dist[ne.first]) {
                    dist[ne.first]=dist[currNode]+ne.second;
                    pq.push({-dist[ne.first], ne.first});
                }
        }
    }

    for(int i=2;i<=n;i++) {
        if(dist[i]==inf)
            g<<0<<' ';
        else
            g<<dist[i]<<' ';
    }

    f.close();
    g.close();
    return 0;
}