Cod sursa(job #2113380)

Utilizator SamySam2099Irsai Samuel SamySam2099 Data 24 ianuarie 2018 15:31:01
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.27 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
int n,m,D[50005];
const int oo=2000000000;
vector<pair <int,int> >G[50005];
struct cmpD{

 bool operator()(int x,int y)
 {
     return D[x]>D[y];
 }

};
priority_queue<int, vector<int>, cmpD>Q;
void read()
{
    f>>n>>m;
    for(int i=1;i<=m;i++)
    {
        int x,y,z;
        f>>x>>y>>z;
        G[x].push_back(make_pair(y,z));
    }
}
bool viz[50005];
void Dijkstra(int nod)
{
    for(int i=1;i<=n;i++)
        if(i!=nod) D[i]=oo;
    Q.push(nod);
    viz[nod]=1;
    while(!Q.empty())
    {
        int x=Q.top();
        Q.pop();
        viz[x]=0;
        for(int i=0;i<(int)G[x].size();i++)
        {
            int vecin=G[x][i].first;
            int cost=G[x][i].second;
            if(D[x]+cost<D[vecin])
            {
                D[vecin]=D[x]+cost;

            if(!viz[vecin])
               {
                   Q.push(vecin);
                    viz[vecin]=1;
               }
            }
        }
    }
}
void show()
{
    for(int i=2;i<=n;i++)
    {
        if(D[i]==oo) g<<"0"<<' ';
        else g<<D[i]<<' ';
    }
}
int main()
{
   read();
   Dijkstra(1);
   show();
}