Cod sursa(job #1379776)

Utilizator rares96cheseliRares Cheseli rares96cheseli Data 6 martie 2015 19:23:48
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.03 kb
#include <fstream>
#include <algorithm>
#include <vector>
#include <queue>
using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");

int N, M, x, D[50005];
const int inf=(1<<30);
struct asd{ int y, c; }aux;
struct cmp
{
    bool operator()(const int &a, const int &b)const
    { return (D[a]>D[b]); }
};
vector < asd > G[50005];
priority_queue <int, vector <int>,cmp > Q;

void dijkstra(int sursa)
{
    Q.push(sursa);
    for (int i=1; i<=N; ++i)
        D[i]=inf; D[sursa]=0;

    while (Q.size())
    {
        int nod=Q.top(); Q.pop();
        vector <asd>::iterator it=G[nod].begin();
        for (; it!=G[nod].end(); ++it)
            if ( D[nod] + it->c < D[it->y] )
                D[it->y]=D[nod]+it->c, 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<<D[i]<<' ';
            else g<<0<<' ';
    return 0;
}