Cod sursa(job #1883296)

Utilizator matystroiaStroia Matei matystroia Data 17 februarie 2017 21:13:22
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.1 kb
#include <algorithm>
#include <fstream>
#include <queue>
#include <vector>
#include <functional>
#include <cstring>
#include <set>
using namespace std;

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

#define INF 50000000

const int N=50000, M=250000;

vector<pair<int,int>> ad[N+1];
int n, m, d[N+1], a, b, c;

int main()
{
    fin>>n>>m;
    for(int i=0;i<m;i++)
    {
        fin>>a>>b>>c;
        ad[a].push_back(make_pair(b, c));
    }

    fill_n(d, n+1, INF);
    d[1] = 0;

    set<pair<int,int>> pq;
    pq.insert(make_pair(0, 1));

    while(!pq.empty())
    {
        int p = pq.begin()->second;
        pq.erase(pq.begin());

        for(auto x : ad[p])
        {
            if (d[p]+x.second<d[x.first])
            {
                if(d[x.first] != INF)
                    pq.erase(pq.find(make_pair(d[x.first], x.first)));
                d[x.first]=d[p]+x.second;
                pq.insert(make_pair(d[x.first], x.first));
            }
        }
    }

    for(int i=2;i<=n;i++)
        fout<<((d[i]==INF)?0:d[i])<<" ";

    return 0;
}