Cod sursa(job #2059489)

Utilizator GladrasGrigoriu Stefan-Cosmin Gladras Data 7 noiembrie 2017 08:36:34
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.39 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>

#define NM 50001
#define INF 2000000000

using namespace std;

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

int n;
int d[NM], inq[NM];

struct arc
{
    int x, y, c;
};

vector<arc> G[NM];

struct compara
{
    bool operator()(int x, int y)
    {
        return d[x]>d[y];
    }
};

priority_queue<int, vector<int>, compara> q;

void Citeste()
{
    int m, i, x;
    fin>>n>>m;
    for(i=1;i<=m;i++)
    {
        arc u;
        fin>>x>>u.y>>u.c;
        G[x].push_back(u);
    }
}

void Dijkstra(int r)
{
    int k, y, c, lg, i;
    for(i=1;i<=n;i++)
        d[i]=INF;
    d[r]=0;

    q.push(r);
    inq[r]=1;

    while(!q.empty())
    {
        k=q.top();
        q.pop();

        inq[k]=0;
        for(i=0;i<G[k].size();i++)
        {
            y=G[k][i].y;
            c=G[k][i].c;
            lg=d[k]+c;
            if(lg<d[y])
            {
                d[y]=lg;
                if(inq[y]==0)
                {
                    q.push(y);
                    inq[y]=1;
                }
            }
        }
    }
    //afisare pentru infoarena
    for(i=2;i<=n;i++)
    {
        if(d[i]!=INF)
            fout<<d[i]<<" ";
        else
            fout<<0<<" ";
    }
}

int main()
{
    Citeste();
    Dijkstra(1);
}