Cod sursa(job #856078)

Utilizator R.A.RFMI Romila Remus Arthur R.A.R Data 15 ianuarie 2013 22:16:31
Problema Algoritmul lui Dijkstra Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 1.12 kb
#include <fstream>
#include <vector>
#include <queue>
#define INF (1<<29)
#define NMAX 50004

using namespace std;

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

int N,M,D[NMAX];

vector<pair<int,int> > V[NMAX];
vector<pair<int,int> >::iterator it,sf;

bool InHeap[NMAX];


class cmp
{
    public:
    inline bool operator()(const int&a,const int&b){return D[a]<D[b];}
};

priority_queue<int,vector<int>,cmp> H;

int main ()
{
    int i,x,y,c,n;
    in>>N>>M;
    while(M--)
    {
        in>>x>>y>>c;
        V[x].push_back(make_pair(y,c));
    }
    for(D[0] = -1,i=2;i<=N;i++)
        D[i] = INF;

    H.push(1);
    while(!H.empty())
    {
        x = H.top();
        InHeap[x] = 0;
        H.pop();
        for(it=V[x].begin(),sf=V[x].end();it<sf;++it)
        {
            y = it->first;
            c = it->second;
            if(D[y] > D[x]+c)
            {

                D[y] = D[x]+c;
                if(!InHeap[y])
                    H.push(y),InHeap[y] = 1;
            }
        }
    }
    for(i=2;i<=N;i++)
        out<<(D[i]!= INF ? D[i] : 0)<<' ';
}