Cod sursa(job #2722595)

Utilizator PopMarcPop Marc PopMarc Data 13 martie 2021 00:21:50
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.6 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

ifstream fin ("dijkstra.in");
ofstream fout ("dijkstra.out");

int a[10000][10000],inf=999999,n,p,x,y,c,m;

int d[50001];
bool v[50001];

vector < pair<int, int> > g[50001];

struct compareDistance {

    bool operator () (int x, int y) {
        return d[x]>d[y];
    }

};

priority_queue <int, vector <int>, compareDistance> q;


int dijkstra (int p) {

    for (int i=1; i<=n; i++) {
        d[i]=inf;
    }
    d[p]=0;
    v[p]=1;
    q.push(p);

    while (!q.empty()) {

        int poz = q.top();
        q.pop();
        v[poz]=0;

        for (int i=0; i<g[poz].size(); i++) {

            int vecin = g[poz][i].first;
            int cost = g[poz][i].second;

            if (d[poz] + cost < d[vecin]) {
                d[vecin]=d[poz] + cost;
                if (v[vecin]==0) {
                    q.push(vecin);
                    v[vecin]=1;
                }
            }
        }
    }

}

int main()
{
    fin>>n>>m;

//    for (int i=1; i<=n; i++) {
//        for (int j=1; j<=n; j++) {
//            if (i==j) a[i][j]=0;
//            else a[i][j]=inf;
//        }
//    }

    for (int i=1; i<=m; i++) {
        fin>>x>>y>>c;
        g[x].push_back(make_pair(y,c));
    }

    dijkstra(1);

//    fout<<"d: ";
    for (int i=2; i<=n; i++) {
        if (d[i]==inf) fout<<0<<" ";
        else fout<<d[i]<<" ";
    }
//    fout<<endl<<"s: ";
//    for (int i=1; i<=n; i++) {
//        fout<<s[i]<<" ";
//    }


    return 0;
}