Cod sursa(job #1118188)

Utilizator rares96cheseliRares Cheseli rares96cheseli Data 24 februarie 2014 08:39:53
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1 kb
#include <fstream>
#include <queue>
#include <vector>
#define inf 2000000000
using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");

int N, M, D[50002], x;
struct muchie{ int y, c;}aux;
struct cmp
{
    bool operator()(const int &a, const int &b)const
    { return (D[a]>D[b]); }
};
priority_queue < int, vector < int >, cmp > Q;
vector < muchie > G[200002];

void dijkstra(int sursa)
{
    for (int i=1; i<=N; ++i)
        D[i]=inf; D[sursa]=0;
    Q.push(sursa);
    while (Q.size())
    {
        int nod=Q.top(); Q.pop();
        vector <muchie>::iterator it=G[nod].begin();
        for (; it!=G[nod].end(); ++it)
            if (D[nod]+ it->c < D[it->y])
                D[it->y]=it->c+D[nod], Q.push(it->y);
    }
}

int main()
{
    f>>N>>M;
    for (int i=1; i<=M; ++i)
        f>>x>>aux.y>>aux.c, G[x].push_back(aux);
    dijkstra(1);
    for (int i=2; i<=N; ++i)
        if (D[i]==inf) g<<0<<' ';
            else g<<D[i]<<' ';
    return 0;
}