Cod sursa(job #1095932)

Utilizator paul_danutDandelion paul_danut Data 1 februarie 2014 11:23:13
Problema Algoritmul lui Dijkstra Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 1.14 kb
#include <fstream>
#include <queue>
#include <vector>
using namespace std;

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

struct muchie{int y,c;}el;

vector<muchie> a[50001];
vector<muchie>::iterator it;


#define INF 99999999
int x,n,m,i,D[50001],viz[50001]={0};

struct cmp{
   bool operator()(int x,int y)
            {return D[x]<D[y];}
};

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

int main()
{
    f>>n>>m;
    for(i=1;i<=m;i++)
        {f>>x>>el.y>>el.c;
        a[x].push_back(el);}

    D[1]=0;
    for(i=2;i<=n;i++)
        D[i]=INF;
    qh.push(1);
    viz[i]++;

    while(!qh.empty())
    {
        x=qh.top();qh.pop();
        if(viz[x]=1)
           {viz[x]--;
           for(it=a[x].begin();it!=a[x].end();++it)
               if( D[it->y]> D[x] + it->c )
                  {
                  D[it->y]= D[x] + it->c;
                  qh.push(it->y);
                  viz[it->y]++;
                  }}
        else
            viz[x]--;
    }

    for(i=2;i<=n;i++)
        if(D[i]==INF)
           g<<0<<' ';
        else
           g<<D[i]<<' ';

    f.close();g.close();
}